--- a/browser/base/content/test/general/browser_bug423833.js
+++ b/browser/base/content/test/general/browser_bug423833.js
@@ -79,26 +79,24 @@ function test2Setup() {
   ok(test2tab, "openFrameInTab() opened a tab");
 
   gBrowser.selectedTab = test2tab;
 
   intervalID = setInterval(testOpenFrameInTab, 3000);
 }
 
 function testOpenFrameInTab() {
-  /* eslint-disable mozilla/no-cpows-in-tests */
   if (gBrowser.contentDocument.location.href == "about:blank")
     // Wait another cycle
     return;
 
   clearInterval(intervalID);
 
   // We should now have the error page in a new, active tab.
   is(gBrowser.contentDocument.location.href, invalidPage, "New tab should have page url, not about:neterror");
-  /* eslint-enable mozilla/no-cpows-in-tests */
 
   // Clear up the new tab, and punt to test 3
   gBrowser.removeCurrentTab();
 
   test3Setup();
 }
 
 function test3Setup() {

--- a/browser/base/content/test/general/browser_bug575561.js
+++ b/browser/base/content/test/general/browser_bug575561.js
@@ -69,17 +69,16 @@ async function testLink(aLinkIndexOrFunc
     });
   } else {
     promise = BrowserTestUtils.browserLoaded(browser, testSubFrame);
   }
 
   let href;
   if (typeof aLinkIndexOrFunction === "function") {
     ok(!browser.isRemoteBrowser, "don't pass a function for a remote browser");
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let link = aLinkIndexOrFunction(browser.contentDocument);
     info("Clicking " + link.textContent);
     link.click();
     href = link.href;
   } else {
     href = await ContentTask.spawn(browser, [ testSubFrame, aLinkIndexOrFunction ], function([ subFrame, index ]) {
       let doc = subFrame ? content.document.querySelector("iframe").contentDocument : content.document;
       let link = doc.querySelectorAll("a")[index];

--- a/browser/base/content/test/general/browser_bug678392.js
+++ b/browser/base/content/test/general/browser_bug678392.js
@@ -31,17 +31,16 @@ function test() {
      "was successfully initialized when supported.");
 
   cleanupArray();
   load(gBrowser.selectedTab, HTTPROOT + "browser_bug678392-2.html", test0);
 }
 
 function load(aTab, aUrl, aCallback) {
   aTab.linkedBrowser.addEventListener("load", function(aEvent) {
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     waitForFocus(aCallback, content);
   }, {capture: true, once: true});
   aTab.linkedBrowser.loadURI(aUrl);
 }
 
 function cleanupArray() {
   let arr = gHistorySwipeAnimation._trackedSnapshots;
   while (arr.length > 0) {

--- a/browser/base/content/test/general/browser_bug767836_perwindowpb.js
+++ b/browser/base/content/test/general/browser_bug767836_perwindowpb.js
@@ -70,17 +70,16 @@ function test() {
   });
 }
 
 function openNewTab(aWindow, aCallback) {
   // Open a new tab
   aWindow.BrowserOpenTab();
 
   let browser = aWindow.gBrowser.selectedBrowser;
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = browser.contentDocumentAsCPOW;
   if (doc && doc.readyState === "complete") {
     executeSoon(aCallback);
     return;
   }
 
   BrowserTestUtils.browserLoaded(browser).then(() => {
     executeSoon(aCallback);

--- a/browser/base/content/test/general/browser_e10s_about_page_triggeringprincipal.js
+++ b/browser/base/content/test/general/browser_e10s_about_page_triggeringprincipal.js
@@ -11,17 +11,16 @@ const kAboutPagesRegistered = Promise.al
     registerCleanupFunction, "test-about-principal-parent", kParentPage,
     Ci.nsIAboutModule.ALLOW_SCRIPT)
 ]);
 
 add_task(async function test_principal_click() {
   await kAboutPagesRegistered;
   await BrowserTestUtils.withNewTab("about:test-about-principal-parent", async function(browser) {
     let loadPromise = BrowserTestUtils.browserLoaded(browser, false, "about:test-about-principal-child");
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let myLink = browser.contentDocument.getElementById("aboutchildprincipal");
     myLink.click();
     await loadPromise;
 
     await ContentTask.spawn(gBrowser.selectedBrowser, {}, async function() {
       let channel = content.document.docShell.currentDocumentChannel;
       is(channel.originalURI.asciiSpec,
          "about:test-about-principal-child",

--- a/browser/base/content/test/general/browser_keywordSearch_postData.js
+++ b/browser/base/content/test/general/browser_keywordSearch_postData.js
@@ -62,17 +62,16 @@ function nextTest() {
     finish();
   }
 }
 
 function doTest() {
   info("Running test: " + gCurrTest.name);
 
   waitForLoad(function() {
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let loadedText = gBrowser.contentDocumentAsCPOW.body.textContent;
     ok(loadedText, "search page loaded");
     let needle = "searchterms=" + gCurrTest.expectText;
     is(loadedText, needle, "The query POST data should be returned in the response");
     nextTest();
   });
 
   // Simulate a user entering search terms

--- a/browser/base/content/test/general/browser_tabfocus.js
+++ b/browser/base/content/test/general/browser_tabfocus.js
@@ -83,17 +83,16 @@ function focusInChild() {
 
   addEventListener("focus", eventListener, true);
   addEventListener("blur", eventListener, true);
 
   addMessageListener("Browser:ChangeFocus", function changeFocus(message) {
     content.document.getElementById(message.data.id)[message.data.type]();
   });
 
-  /* eslint-disable mozilla/no-cpows-in-tests */
   addMessageListener("Browser:GetFocusedElement", function getFocusedElement(message) {
     var focusedWindow = {};
     var node = Services.focus.getFocusedElementForWindow(content, false, focusedWindow);
     var details = "Focus is " + (node ? node.id : "<none>");
 
     /* Check focus manager properties. Add an error onto the string if they are
        not what is expected which will cause matching to fail in the parent process. */
     let doc = content.document;
@@ -121,17 +120,16 @@ function focusElementInChild(elementid, 
   let browser = (elementid.includes("1")) ? browser1 : browser2;
   if (gMultiProcessBrowser) {
     browser.messageManager.sendAsyncMessage("Browser:ChangeFocus",
                                             { id: elementid, type });
   } else {
     browser.contentDocument.getElementById(elementid)[type]();
   }
 }
-/* eslint-enable mozilla/no-cpows-in-tests */
 
 add_task(async function() {
   tab1 = BrowserTestUtils.addTab(gBrowser);
   browser1 = gBrowser.getBrowserForTab(tab1);
 
   tab2 = BrowserTestUtils.addTab(gBrowser);
   browser2 = gBrowser.getBrowserForTab(tab2);
 

--- a/browser/base/content/test/pageinfo/browser_pageinfo_image_info.js
+++ b/browser/base/content/test/pageinfo/browser_pageinfo_image_info.js
@@ -20,17 +20,16 @@ const URI =
 function test() {
   waitForExplicitFinish();
 
   gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser);
 
   let uriToWaitFor = URI.replace(/ /g, "%20");
   BrowserTestUtils.browserLoaded(gBrowser.selectedBrowser, false,
                                  uriToWaitFor).then(function() {
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     var doc = gBrowser.contentDocumentAsCPOW;
     var testImg = doc.getElementById("test-image");
     var pageInfo = BrowserPageInfo(gBrowser.selectedBrowser.currentURI.spec,
                                    "mediaTab", getImageInfo(testImg));
 
     pageInfo.addEventListener("load", function() {
       pageInfo.onFinished.push(function() {
         var pageInfoImg = pageInfo.document.getElementById("thepreviewimage");

--- a/browser/base/content/test/popupNotifications/browser_popupNotification_keyboard.js
+++ b/browser/base/content/test/popupNotifications/browser_popupNotification_keyboard.js
@@ -187,17 +187,16 @@ var tests = [
         await opened;
 
         // Check that the focused element in the chrome window
         // is either the browser in case we're running on e10s
         // or the input field in case of non-e10s.
         if (gMultiProcessBrowser) {
           is(Services.focus.focusedElement, browser);
         } else {
-          // eslint-disable-next-line mozilla/no-cpows-in-tests
           is(Services.focus.focusedElement, browser.contentDocument.getElementById("test-input"));
         }
 
         // Check that the input field is still focused inside the browser.
         await ContentTask.spawn(browser, {}, function() {
           is(content.document.activeElement, content.document.getElementById("test-input"));
         });
 

--- a/browser/base/content/test/sidebar/browser_bug409481.js
+++ b/browser/base/content/test/sidebar/browser_bug409481.js
@@ -32,21 +32,19 @@ function delayedRunTest() {
   setTimeout(runTest, 100);
 }
 
 function runTest(event) {
   var sidebar = document.getElementById("sidebar");
   sidebar.contentDocument.removeEventListener("load", delayedRunTest, true);
 
   var browser = sidebar.contentDocument.getElementById("web-panels-browser");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   var div = browser && browser.contentDocument.getElementById("test_bug409481");
   ok(div && div.textContent == "Content!", "Sidebar content loaded");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   var link = browser && browser.contentDocument.getElementById("link");
   sidebar.contentDocument.addEventListener("popupshown", contextMenuOpened);
 
   EventUtils.synthesizeMouseAtCenter(link, { type: "contextmenu", button: 2 }, browser.contentWindow);
 }
 
 function contextMenuOpened() {
   var sidebar = document.getElementById("sidebar");
@@ -57,17 +55,16 @@ function contextMenuOpened() {
   copyLinkCommand.doCommand();
 }
 
 function copyLinkCommandExecuted(event) {
   event.target.removeEventListener("command", copyLinkCommandExecuted);
 
   var sidebar = document.getElementById("sidebar");
   var browser = sidebar.contentDocument.getElementById("web-panels-browser");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   var textbox = browser && browser.contentDocument.getElementById("textbox");
   textbox.focus();
   document.commandDispatcher.getControllerForCommand("cmd_paste").doCommand("cmd_paste");
   is(textbox.value, "http://www.example.com/ctest", "copy link command");
 
   sidebar.contentDocument.addEventListener("popuphidden", contextMenuClosed);
   event.target.parentNode.hidePopup();
 }

--- a/browser/base/content/test/siteIdentity/browser_bug906190.js
+++ b/browser/base/content/test/siteIdentity/browser_bug906190.js
@@ -29,28 +29,25 @@ async function doTest(parentTabSpec, chi
     });
 
     // Disable the Mixed Content Blocker for the page, which reloads it.
     let promiseReloaded = BrowserTestUtils.browserLoaded(browser);
     gIdentityHandler.disableMixedContentProtection();
     await promiseReloaded;
 
     // Wait for the script in the page to update the contents of the test div.
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let testDiv = gBrowser.contentDocumentAsCPOW.getElementById("mctestdiv");
     await BrowserTestUtils.waitForCondition(
       () => testDiv.innerHTML == "Mixed Content Blocker disabled");
 
     // Add the link for the child tab to the page.
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let mainDiv = gBrowser.contentDocumentAsCPOW.createElement("div");
     // eslint-disable-next-line no-unsanitized/property
     mainDiv.innerHTML =
       '<p><a id="linkToOpenInNewTab" href="' + childTabSpec + '">Link</a></p>';
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     gBrowser.contentDocumentAsCPOW.body.appendChild(mainDiv);
 
     // Execute the test in the child tabs with the two methods to open it.
     for (let openFn of [simulateCtrlClick, simulateContextMenuOpenInTab]) {
       let promiseTabLoaded = waitForSomeTabToLoad();
       openFn(browser);
       await promiseTabLoaded;
       gBrowser.selectTabAtIndex(2);
@@ -114,17 +111,16 @@ add_task(async function test_same_origin
                HTTPS_TEST_ROOT_1 + "file_bug906190_2.html", async function() {
     // The doorhanger should appear but activeBlocked should be >> NOT << true,
     // because our decision of disabling the mixed content blocker is persistent
     // across tabs.
     await assertMixedContentBlockingState(gBrowser, {
       activeLoaded: true, activeBlocked: false, passiveLoaded: false,
     });
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     is(gBrowser.contentDocumentAsCPOW.getElementById("mctestdiv").innerHTML,
        "Mixed Content Blocker disabled", "OK: Executed mixed script");
   });
 });
 
 /**
  * 2. - Load a html page which has mixed content
  *    - Doorhanger to disable protection appears - we disable it
@@ -136,17 +132,16 @@ add_task(async function test_different_o
                HTTPS_TEST_ROOT_2 + "file_bug906190_2.html", async function() {
     // The doorhanger should appear and activeBlocked should be >> TRUE <<,
     // because our decision of disabling the mixed content blocker should only
     // persist if pages are from the same domain.
     await assertMixedContentBlockingState(gBrowser, {
       activeLoaded: false, activeBlocked: true, passiveLoaded: false,
     });
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     is(gBrowser.contentDocumentAsCPOW.getElementById("mctestdiv").innerHTML,
        "Mixed Content Blocker enabled", "OK: Blocked mixed script");
   });
 });
 
 /**
  * 3. - Load a html page which has mixed content
  *    - Doorhanger to disable protection appears - we disable it
@@ -158,17 +153,16 @@ add_task(async function test_same_origin
   // file_bug906190_3_4.html redirects to page test1.example.com/* using meta-refresh
   await doTest(HTTPS_TEST_ROOT_1 + "file_bug906190_1.html",
                HTTPS_TEST_ROOT_1 + "file_bug906190_3_4.html", async function() {
     // The doorhanger should appear but activeBlocked should be >> NOT << true!
     await assertMixedContentBlockingState(gBrowser, {
       activeLoaded: true, activeBlocked: false, passiveLoaded: false,
     });
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     is(gBrowser.contentDocumentAsCPOW.getElementById("mctestdiv").innerHTML,
        "Mixed Content Blocker disabled", "OK: Executed mixed script");
   }, true);
 });
 
 /**
  * 4. - Load a html page which has mixed content
  *    - Doorhanger to disable protection appears - we disable it
@@ -179,17 +173,16 @@ add_task(async function test_same_origin
 add_task(async function test_same_origin_metarefresh_different_origin() {
   await doTest(HTTPS_TEST_ROOT_2 + "file_bug906190_1.html",
                HTTPS_TEST_ROOT_2 + "file_bug906190_3_4.html", async function() {
     // The doorhanger should appear and activeBlocked should be >> TRUE <<.
     await assertMixedContentBlockingState(gBrowser, {
       activeLoaded: false, activeBlocked: true, passiveLoaded: false,
     });
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     is(gBrowser.contentDocumentAsCPOW.getElementById("mctestdiv").innerHTML,
        "Mixed Content Blocker enabled", "OK: Blocked mixed script");
   }, true);
 });
 
 /**
  * 5. - Load a html page which has mixed content
  *    - Doorhanger to disable protection appears - we disable it
@@ -200,17 +193,16 @@ add_task(async function test_same_origin
   // the sjs files returns a 302 redirect- note, same origins
   await doTest(HTTPS_TEST_ROOT_1 + "file_bug906190_1.html",
                HTTPS_TEST_ROOT_1 + "file_bug906190.sjs", function() {
     // The doorhanger should appear but activeBlocked should be >> NOT << true.
     // Currently it is >> TRUE << - see follow up bug 914860
     ok(!gIdentityHandler._identityBox.classList.contains("mixedActiveBlocked"),
        "OK: Mixed Content is NOT being blocked");
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     is(gBrowser.contentDocumentAsCPOW.getElementById("mctestdiv").innerHTML,
        "Mixed Content Blocker disabled", "OK: Executed mixed script");
   });
 });
 
 /**
  * 6. - Load a html page which has mixed content
  *    - Doorhanger to disable protection appears - we disable it
@@ -221,17 +213,16 @@ add_task(async function test_same_origin
   // the sjs files returns a 302 redirect - note, different origins
   await doTest(HTTPS_TEST_ROOT_2 + "file_bug906190_1.html",
                HTTPS_TEST_ROOT_2 + "file_bug906190.sjs", async function() {
     // The doorhanger should appear and activeBlocked should be >> TRUE <<.
     await assertMixedContentBlockingState(gBrowser, {
       activeLoaded: false, activeBlocked: true, passiveLoaded: false,
     });
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     is(gBrowser.contentDocumentAsCPOW.getElementById("mctestdiv").innerHTML,
        "Mixed Content Blocker enabled", "OK: Blocked mixed script");
   });
 });
 
 /**
  * 7. - Test memory leak issue on redirection error. See Bug 1269426.
  */

--- a/browser/base/content/test/tabcrashed/browser_autoSubmitRequest.js
+++ b/browser/base/content/test/tabcrashed/browser_autoSubmitRequest.js
@@ -27,17 +27,16 @@ add_task(async function test_show_form()
   }, async function(browser) {
     // Make sure we've flushed the browser messages so that
     // we can restore it.
     await TabStateFlusher.flush(browser);
 
     // Now crash the browser.
     await BrowserTestUtils.crashBrowser(browser);
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = browser.contentDocument;
 
     // Ensure the request is visible. We can safely reach into
     // the content since about:tabcrashed is an in-process URL.
     let requestAutoSubmit = doc.getElementById("requestAutoSubmit");
     Assert.ok(!requestAutoSubmit.hidden,
               "Request for autosubmission is visible.");
 
@@ -72,17 +71,16 @@ add_task(async function test_show_form()
   await BrowserTestUtils.withNewTab({
     gBrowser,
     url: PAGE,
   }, async function(browser) {
     await TabStateFlusher.flush(browser);
     // Now crash the browser.
     await BrowserTestUtils.crashBrowser(browser);
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = browser.contentDocument;
 
     // Ensure the request is NOT visible. We can safely reach into
     // the content since about:tabcrashed is an in-process URL.
     let requestAutoSubmit = doc.getElementById("requestAutoSubmit");
     Assert.ok(requestAutoSubmit.hidden,
               "Request for autosubmission is not visible.");
 
@@ -117,17 +115,16 @@ add_task(async function test_no_offer() 
     await TabStateFlusher.flush(browser);
 
     // Make it so that it seems like no dump is available for the next crash.
     prepareNoDump();
 
     // Now crash the browser.
     await BrowserTestUtils.crashBrowser(browser);
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = browser.contentDocument;
 
     // Ensure the request to autosubmit is invisible, since there's no report.
     let requestRect = doc.getElementById("requestAutoSubmit")
                          .getBoundingClientRect();
     Assert.equal(0, requestRect.height,
                  "Request for autosubmission has no height");
     Assert.equal(0, requestRect.width,

--- a/browser/base/content/test/tabcrashed/browser_clearEmail.js
+++ b/browser/base/content/test/tabcrashed/browser_clearEmail.js
@@ -32,29 +32,27 @@ add_task(async function test_clear_email
     // crash
     prefs.setCharPref("email", EMAIL);
     prefs.setBoolPref("emailMe", true);
 
     let tab = gBrowser.getTabForBrowser(browser);
     await BrowserTestUtils.crashBrowser(browser,
                                         /* shouldShowTabCrashPage */ true,
                                         /* shouldClearMinidumps */ false);
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = browser.contentDocument;
 
     // Since about:tabcrashed will run in the parent process, we can safely
     // manipulate its DOM nodes directly
     let emailMe = doc.getElementById("emailMe");
     emailMe.checked = false;
 
     let crashReport = promiseCrashReport({
       Email: "",
     });
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let restoreTab = browser.contentDocument.getElementById("restoreTab");
     restoreTab.click();
     await BrowserTestUtils.waitForEvent(tab, "SSTabRestored");
     await crashReport;
 
     is(prefs.getCharPref("email"), "", "No email address should be stored");
 
     // Submitting the crash report may have set some prefs regarding how to

--- a/browser/base/content/test/tabcrashed/browser_showForm.js
+++ b/browser/base/content/test/tabcrashed/browser_showForm.js
@@ -21,17 +21,16 @@ add_task(async function test_show_form()
     let pref = TabCrashHandler.prefs.root + "sendReport";
     await SpecialPowers.pushPrefEnv({
       set: [[pref, true]]
     });
 
     // Now crash the browser.
     await BrowserTestUtils.crashBrowser(browser);
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = browser.contentDocument;
 
     // Ensure the checkbox is checked. We can safely reach into
     // the content since about:tabcrashed is an in-process URL.
     let checkbox = doc.getElementById("sendReport");
     ok(checkbox.checked, "Send report checkbox is checked.");
 
     // Ensure the options form is displayed.

--- a/browser/base/content/test/tabcrashed/browser_shown.js
+++ b/browser/base/content/test/tabcrashed/browser_shown.js
@@ -51,17 +51,16 @@ function crashTabTestHelper(fieldValues,
     let prefs = TabCrashHandler.prefs;
     let originalSendReport = prefs.getBoolPref("sendReport");
     let originalEmailMe = prefs.getBoolPref("emailMe");
     let originalIncludeURL = prefs.getBoolPref("includeURL");
     let originalEmail = prefs.getCharPref("email");
 
     let tab = gBrowser.getTabForBrowser(browser);
     await BrowserTestUtils.crashBrowser(browser);
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = browser.contentDocument;
 
     // Since about:tabcrashed will run in the parent process, we can safely
     // manipulate its DOM nodes directly
     let comments = doc.getElementById("comments");
     let email = doc.getElementById("email");
     let emailMe = doc.getElementById("emailMe");
     let includeURL = doc.getElementById("includeURL");
@@ -78,17 +77,16 @@ function crashTabTestHelper(fieldValues,
       emailMe.checked = fieldValues.emailMe;
     }
 
     if (fieldValues.hasOwnProperty("includeURL")) {
       includeURL.checked = fieldValues.includeURL;
     }
 
     let crashReport = promiseCrashReport(expectedExtra);
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let restoreTab = browser.contentDocument.getElementById("restoreTab");
     restoreTab.click();
     await BrowserTestUtils.waitForEvent(tab, "SSTabRestored");
     await crashReport;
 
     // Submitting the crash report may have set some prefs regarding how to
     // send tab crash reports. Let's reset them for the next test.
     prefs.setBoolPref("sendReport", originalSendReport);

--- a/browser/base/content/test/urlbar/browser_urlbarKeepStateAcrossTabSwitches.js
+++ b/browser/base/content/test/urlbar/browser_urlbarKeepStateAcrossTabSwitches.js
@@ -5,17 +5,16 @@
  * loads fail.
  */
 add_task(async function() {
   let input = "i-definitely-dont-exist.example.com";
   let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, "about:blank", false);
   let browser = tab.linkedBrowser;
   // NB: CPOW usage because new tab pages can be preloaded, in which case no
   // load events fire.
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   await BrowserTestUtils.waitForCondition(() => browser.contentDocumentAsCPOW && !browser.contentDocumentAsCPOW.hidden);
   let errorPageLoaded = BrowserTestUtils.waitForErrorPage(tab.linkedBrowser);
   gURLBar.value = input;
   gURLBar.select();
   EventUtils.sendKey("return");
   await errorPageLoaded;
   is(gURLBar.textValue, input, "Text is still in URL bar");
   await BrowserTestUtils.switchTab(gBrowser, tab.previousSibling);
@@ -30,17 +29,16 @@ add_task(async function() {
  */
 add_task(async function() {
   let input = "To be or not to be-that is the question";
   await SpecialPowers.pushPrefEnv({set: [["keyword.enabled", false]]});
   let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, "about:blank", false);
   let browser = tab.linkedBrowser;
   // NB: CPOW usage because new tab pages can be preloaded, in which case no
   // load events fire.
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   await BrowserTestUtils.waitForCondition(() => browser.contentDocumentAsCPOW && !browser.contentDocumentAsCPOW.hidden);
   let errorPageLoaded = BrowserTestUtils.waitForErrorPage(tab.linkedBrowser);
   gURLBar.value = input;
   gURLBar.select();
   EventUtils.sendKey("return");
   await errorPageLoaded;
   is(gURLBar.textValue, input, "Text is still in URL bar");
   is(tab.linkedBrowser.userTypedValue, input, "Text still stored on browser");

--- a/browser/base/content/test/webextensions/browser_extension_sideloading.js
+++ b/browser/base/content/test/webextensions/browser_extension_sideloading.js
@@ -131,17 +131,16 @@ add_task(async function() {
   ok(PanelUI.panel.state != "open", "Main menu is closed or closing.");
 
   // When we get the permissions prompt, we should be at the extensions
   // list in about:addons
   let panel = await popupPromise;
   is(gBrowser.currentURI.spec, "about:addons", "Foreground tab is at about:addons");
 
   const VIEW = "addons://list/extension";
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let win = gBrowser.selectedBrowser.contentWindow;
   ok(!win.gViewController.isLoading, "about:addons view is fully loaded");
   is(win.gViewController.currentViewId, VIEW, "about:addons is at extensions list");
 
   // Check the contents of the notification, then choose "Cancel"
   checkNotification(panel, /\/foo-icon\.png$/, [
     ["webextPerms.hostDescription.allUrls"],
     ["webextPerms.description.history"],
@@ -167,17 +166,16 @@ add_task(async function() {
   // Click the second sideloaded extension and wait for the notification
   popupPromise = promisePopupNotificationShown("addon-webext-permissions");
   addons.children[0].click();
   panel = await popupPromise;
 
   // Again we should be at the extentions list in about:addons
   is(gBrowser.currentURI.spec, "about:addons", "Foreground tab is at about:addons");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   win = gBrowser.selectedBrowser.contentWindow;
   ok(!win.gViewController.isLoading, "about:addons view is fully loaded");
   is(win.gViewController.currentViewId, VIEW, "about:addons is at extensions list");
 
   // Check the notification contents.
   checkNotification(panel, DEFAULT_ICON_URL, []);
 
   // This time accept the install.

--- a/browser/components/contextualidentity/test/browser/browser_usercontext.js
+++ b/browser/components/contextualidentity/test/browser/browser_usercontext.js
@@ -64,17 +64,16 @@ add_task(async function test() {
 
     let tab = openTabInUserContext(BASE_URI, userContextId);
 
     // wait for load
     let browser = gBrowser.getBrowserForTab(tab);
     await BrowserTestUtils.browserLoaded(browser);
 
     // get the title
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let title = browser.contentDocumentAsCPOW.title.trim().split("|");
 
     // check each item in the title and validate it meets expectatations
     for (let part of title) {
       let [storageMethodName, value] = part.split("=");
       is(value, expectedContext,
             "the title reflects the expected contextual identity of " +
             expectedContext + " for method " + storageMethodName + ": " + value);

--- a/browser/components/customizableui/test/browser_947914_button_addons.js
+++ b/browser/components/customizableui/test/browser_947914_button_addons.js
@@ -19,17 +19,16 @@ add_task(async function() {
   let addonsButton = document.getElementById("add-ons-button");
   ok(addonsButton, "Add-ons button exists in Panel Menu");
   addonsButton.click();
 
   newTab = gBrowser.selectedTab;
   await waitForCondition(() => gBrowser.currentURI &&
                                gBrowser.currentURI.spec == "about:addons");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let addonsPage = gBrowser.selectedBrowser.contentWindow.document.
                             getElementById("addons-page");
   ok(addonsPage, "Add-ons page was opened");
 });
 
 add_task(async function asyncCleanup() {
   CustomizableUI.reset();
   BrowserTestUtils.addTab(gBrowser, initialLocation);

--- a/browser/components/enterprisepolicies/tests/browser/browser_policies_notice_in_aboutpreferences.js
+++ b/browser/components/enterprisepolicies/tests/browser/browser_policies_notice_in_aboutpreferences.js
@@ -4,13 +4,12 @@
 "use strict";
 
 add_task(async function test_notice_in_aboutprefences() {
   await setupPolicyEngineWithJson({
     "policies": { }
   });
 
   await BrowserTestUtils.withNewTab("about:preferences", async browser => {
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   ok(!browser.contentDocument.getElementById("policies-container").hidden,
      "The Policies notice was made visible in about:preferences");
   });
 });

--- a/browser/components/enterprisepolicies/tests/browser/browser_policy_disable_masterpassword.js
+++ b/browser/components/enterprisepolicies/tests/browser/browser_policy_disable_masterpassword.js
@@ -32,17 +32,16 @@ async function checkDeviceManager({butto
   is(changePwButton.getAttribute("disabled") == "true", buttonIsDisabled,
      "Change Password button is in the correct state: " + buttonIsDisabled);
 
   await BrowserTestUtils.closeWindow(deviceManagerWindow);
 }
 
 async function checkAboutPreferences({checkboxIsDisabled}) {
   await BrowserTestUtils.withNewTab("about:preferences#privacy", async browser => {
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   is(browser.contentDocument.getElementById("useMasterPassword").disabled, checkboxIsDisabled,
     "Master Password checkbox is in the correct state: " + checkboxIsDisabled);
 });
 
 }
 
 add_task(async function test_policy_disable_masterpassword() {
   ok(!mpToken.hasPassword, "Starting the test with no password");

--- a/browser/components/extensions/test/browser/browser_ext_browserAction_popup_resize.js
+++ b/browser/components/extensions/test/browser/browser_ext_browserAction_popup_resize.js
@@ -36,22 +36,20 @@ add_task(async function testBrowserActio
 
     // Tolerate if it is 1px too wide, as that may happen with the current resizing method.
     Assert.lessOrEqual(Math.abs(dims.window.innerWidth - expected), 1,
                        `Panel window should be ${expected}px wide`);
     is(dims.body.clientWidth, dims.body.scrollWidth,
        "Panel body should be wide enough to fit its contents");
   }
 
-  /* eslint-disable mozilla/no-cpows-in-tests */
   function setSize(size) {
     content.document.body.style.height = `${size}px`;
     content.document.body.style.width = `${size}px`;
   }
-  /* eslint-enable mozilla/no-cpows-in-tests */
 
   let sizes = [
     200,
     400,
     300,
   ];
 
   for (let size of sizes) {
@@ -110,18 +108,16 @@ async function testPopupSize(standardsMo
             <span></span>
           </body>
         </html>`,
     },
   });
 
   await extension.startup();
 
-  /* eslint-disable mozilla/no-cpows-in-tests */
-
   if (arrowSide == "top") {
     // Test the standalone panel for a toolbar button.
     let browser = await openPanel(extension, browserWin, true);
 
     let dims = await promiseContentDimensions(browser);
 
     is(dims.isStandards, standardsMode, "Document has the expected compat mode");
 

--- a/browser/components/extensions/test/browser/browser_ext_find.js
+++ b/browser/components/extensions/test/browser/browser_ext_find.js
@@ -1,12 +1,11 @@
 /* global browser */
 "use strict";
 
-/* eslint-disable mozilla/no-cpows-in-tests */
 function frameScript() {
   function getSelectedText() {
     let frame = this.content.frames[0].frames[1];
     let docShell = frame.QueryInterface(Ci.nsIInterfaceRequestor)
                         .getInterface(Ci.nsIWebNavigation)
                         .QueryInterface(Ci.nsIDocShell);
     let controller = docShell.QueryInterface(Ci.nsIInterfaceRequestor)
                              .getInterface(Ci.nsISelectionDisplay)
@@ -24,17 +23,16 @@ function frameScript() {
     let rect = {
       top: (r1.top + r2.top + r3.top + f1.y + f2.y),
       left: (r1.left + r2.left + r3.left + f1.x + f2.x),
     };
     this.sendAsyncMessage("test:find:selectionTest", {text: selection.toString(), rect});
   }
   getSelectedText();
 }
-/* eslint-enable mozilla/no-cpows-in-tests */
 
 function waitForMessage(messageManager, topic) {
   return new Promise(resolve => {
     messageManager.addMessageListener(topic, function messageListener(message) {
       messageManager.removeMessageListener(topic, messageListener);
       resolve(message);
     });
   });

--- a/browser/components/extensions/test/browser/browser_ext_omnibox.js
+++ b/browser/components/extensions/test/browser/browser_ext_omnibox.js
@@ -1,18 +1,12 @@
 /* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
 /* vim: set sts=2 sw=2 et tw=80: */
 "use strict";
 
-// The no-cpows-in-tests check isn't very smart, simply warning if it finds
-// a variable named `content`. For Chrome compatibility, the Omnibox API uses
-// that name for setting the text of a suggestion, and that's all this test uses
-// it for, so we can disable it for this test.
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 add_task(async function() {
   let keyword = "test";
 
   let extension = ExtensionTestUtils.loadExtension({
     manifest: {
       "omnibox": {
         "keyword": keyword,
       },

--- a/browser/components/extensions/test/browser/browser_ext_pageAction_popup_resize.js
+++ b/browser/components/extensions/test/browser/browser_ext_pageAction_popup_resize.js
@@ -46,23 +46,21 @@ add_task(async function testPageActionPo
        "Panel root should be tall enough to fit its contents");
 
     // Tolerate if it is 1px too wide, as that may happen with the current resizing method.
     ok(Math.abs(dims.window.innerWidth - expected) <= 1, `Panel window should be ${expected}px wide`);
     is(body.clientWidth, body.scrollWidth,
        "Panel body should be wide enough to fit its contents");
   }
 
-  /* eslint-disable mozilla/no-cpows-in-tests */
   function setSize(size) {
     let elem = content.document.body.firstChild;
     elem.style.height = `${size}px`;
     elem.style.width = `${size}px`;
   }
-  /* eslint-enable mozilla/no-cpows-in-tests */
 
   let sizes = [
     200,
     400,
     300,
   ];
 
   for (let size of sizes) {
@@ -119,21 +117,19 @@ add_task(async function testPageActionPo
 
   await extension.startup();
   await extension.awaitMessage("action-shown");
 
   clickPageAction(extension, window);
 
   browser = await awaitExtensionPanel(extension);
 
-  /* eslint-disable mozilla/no-cpows-in-tests */
   function setSize(size) {
     content.document.body.style.fontSize = `${size}px`;
   }
-  /* eslint-enable mozilla/no-cpows-in-tests */
 
   let dims = await alterContent(browser, setSize, 18);
 
   is(dims.window.innerWidth, 800, "Panel window should be 800px wide");
   is(dims.body.clientWidth, 800, "Panel body should be 800px wide");
   is(dims.body.clientWidth, dims.body.scrollWidth,
      "Panel body should be wide enough to fit its contents");
 

--- a/browser/components/extensions/test/browser/browser_ext_popup_background.js
+++ b/browser/components/extensions/test/browser/browser_ext_popup_background.js
@@ -54,21 +54,19 @@ add_task(async function testPopupBackgro
 
     function getBackground(browser) {
       return ContentTask.spawn(browser, null, async function() {
         return content.getComputedStyle(content.document.body)
                       .backgroundColor;
       });
     }
 
-    /* eslint-disable mozilla/no-cpows-in-tests */
     let setBackground = color => {
       content.document.body.style.backgroundColor = color;
     };
-    /* eslint-enable mozilla/no-cpows-in-tests */
 
     await new Promise(resolve => setTimeout(resolve, 100));
 
     info("Test that initial background color is applied");
 
     checkArrow(await getBackground(browser));
 
     info("Test that dynamically-changed background color is applied");

--- a/browser/components/extensions/test/browser/browser_ext_popup_corners.js
+++ b/browser/components/extensions/test/browser/browser_ext_popup_corners.js
@@ -41,23 +41,21 @@ add_task(async function testPopupBorderR
 
     let stack = browser.parentNode;
     let viewNode = stack.parentNode === panel ? browser : stack.parentNode;
     let viewStyle = getComputedStyle(viewNode);
 
     let props = ["borderTopLeftRadius", "borderTopRightRadius",
                  "borderBottomRightRadius", "borderBottomLeftRadius"];
 
-    /* eslint-disable mozilla/no-cpows-in-tests */
     let bodyStyle = await ContentTask.spawn(browser, props, async function(props) {
       let bodyStyle = content.getComputedStyle(content.document.body);
 
       return new Map(props.map(prop => [prop, bodyStyle[prop]]));
     });
-    /* eslint-enable mozilla/no-cpows-in-tests */
 
     for (let prop of props) {
       if (standAlone) {
         is(viewStyle[prop], panelStyle[prop], `Panel and view ${prop} should be the same`);
         is(bodyStyle.get(prop), panelStyle[prop], `Panel and body ${prop} should be the same`);
       } else {
         is(viewStyle[prop], "0px", `View node ${prop} should be 0px`);
         is(bodyStyle.get(prop), "0px", `Body node ${prop} should be 0px`);

--- a/browser/components/extensions/test/browser/browser_ext_webNavigation_onCreatedNavigationTarget.js
+++ b/browser/components/extensions/test/browser/browser_ext_webNavigation_onCreatedNavigationTarget.js
@@ -117,17 +117,17 @@ add_task(async function test_on_created_
   info("Open a subframe link in a new tab using Ctrl-click");
 
   await runCreatedNavigationTargetTest({
     extension,
     openNavTarget() {
       BrowserTestUtils.synthesizeMouseAtCenter(function() {
         // This code runs as a framescript in the child process and it returns the
         // target link in the subframe.
-        return this.content.frames[0].document // eslint-disable-line mozilla/no-cpows-in-tests
+        return this.content.frames[0].document
           .querySelector("#test-create-new-tab-from-mouse-click-subframe");
       }, {ctrlKey: true, metaKey: true}, tab.linkedBrowser);
     },
     expectedWebNavProps: {
       sourceTabId: expectedSourceTab.sourceTabId,
       sourceFrameId: expectedSourceTab.sourceTabFrames[1].frameId,
       url: `${OPENED_PAGE}#new-tab-from-mouse-click-subframe`,
     },
@@ -136,17 +136,17 @@ add_task(async function test_on_created_
   info("Open a subframe link in a new window using Shift-click");
 
   await runCreatedNavigationTargetTest({
     extension,
     openNavTarget() {
       BrowserTestUtils.synthesizeMouseAtCenter(function() {
         // This code runs as a framescript in the child process and it returns the
         // target link in the subframe.
-        return this.content.frames[0].document // eslint-disable-line mozilla/no-cpows-in-tests
+        return this.content.frames[0].document
                       .querySelector("#test-create-new-window-from-mouse-click-subframe");
       }, {shiftKey: true}, tab.linkedBrowser);
     },
     expectedWebNavProps: {
       sourceTabId: expectedSourceTab.sourceTabId,
       sourceFrameId: expectedSourceTab.sourceTabFrames[1].frameId,
       url: `${OPENED_PAGE}#new-window-from-mouse-click-subframe`,
     },
@@ -155,17 +155,17 @@ add_task(async function test_on_created_
   info("Open a subframe link with target=\"_blank\" in a new tab using click");
 
   await runCreatedNavigationTargetTest({
     extension,
     openNavTarget() {
       BrowserTestUtils.synthesizeMouseAtCenter(function() {
         // This code runs as a framescript in the child process and it returns the
         // target link in the subframe.
-        return this.content.frames[0].document // eslint-disable-line mozilla/no-cpows-in-tests
+        return this.content.frames[0].document
           .querySelector("#test-create-new-tab-from-targetblank-click-subframe");
       }, {}, tab.linkedBrowser);
     },
     expectedWebNavProps: {
       sourceTabId: expectedSourceTab.sourceTabId,
       sourceFrameId: expectedSourceTab.sourceTabFrames[1].frameId,
       url: `${OPENED_PAGE}#new-tab-from-targetblank-click-subframe`,
     },

--- a/browser/components/extensions/test/browser/browser_ext_webNavigation_onCreatedNavigationTarget_contextmenu.js
+++ b/browser/components/extensions/test/browser/browser_ext_webNavigation_onCreatedNavigationTarget_contextmenu.js
@@ -112,17 +112,17 @@ add_task(async function test_on_created_
 
   await runCreatedNavigationTargetTest({
     extension,
     async openNavTarget() {
       await clickContextMenuItem({
         pageElementSelector: function() {
           // This code runs as a framescript in the child process and it returns the
           // target link in the subframe.
-          return this.content.frames[0] // eslint-disable-line mozilla/no-cpows-in-tests
+          return this.content.frames[0]
             .document.querySelector("#test-create-new-tab-from-context-menu-subframe");
         },
         contextMenuItemLabel: "Open Link in New Tab",
       });
     },
     expectedWebNavProps: {
       sourceTabId: expectedSourceTab.sourceTabId,
       sourceFrameId: expectedSourceTab.sourceTabFrames[1].frameId,
@@ -134,17 +134,17 @@ add_task(async function test_on_created_
 
   await runCreatedNavigationTargetTest({
     extension,
     async openNavTarget() {
       await clickContextMenuItem({
         pageElementSelector: function() {
           // This code runs as a framescript in the child process and it returns the
           // target link in the subframe.
-          return this.content.frames[0] // eslint-disable-line mozilla/no-cpows-in-tests
+          return this.content.frames[0]
             .document.querySelector("#test-create-new-window-from-context-menu-subframe");
         },
         contextMenuItemLabel: "Open Link in New Window",
       });
     },
     expectedWebNavProps: {
       sourceTabId: expectedSourceTab.sourceTabId,
       sourceFrameId: expectedSourceTab.sourceTabFrames[1].frameId,

--- a/browser/components/preferences/in-content/tests/browser_advanced_update.js
+++ b/browser/components/preferences/in-content/tests/browser_advanced_update.js
@@ -106,17 +106,16 @@ add_task(async function() {
   gBrowser.removeCurrentTab();
 });
 
 add_task(async function() {
   await openPreferencesViaOpenPreferencesAPI("general", { leaveOpen: true });
   let doc = gBrowser.selectedBrowser.contentDocument;
 
   let showBtn = doc.getElementById("showUpdateHistory");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let dialogOverlay = content.gSubDialog._preloadDialog._overlay;
 
   // XXX: For unknown reasons, this mock cannot be loaded by
   // XPCOMUtils.defineLazyServiceGetter() called in aboutDialog-appUpdater.js.
   // It is registered here so that we could assert update history subdialog
   // without stopping the preferences advanced pane from loading.
   // See bug 1361929.
   mockUpdateManager.register();

--- a/browser/components/preferences/in-content/tests/browser_applications_selection.js
+++ b/browser/components/preferences/in-content/tests/browser_applications_selection.js
@@ -3,27 +3,25 @@ var feedItem;
 var container;
 
 SimpleTest.requestCompleteLog();
 
 add_task(async function setup() {
   await openPreferencesViaOpenPreferencesAPI("general", { leaveOpen: true });
   info("Preferences page opened on the general pane.");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   await gBrowser.selectedBrowser.contentWindow.promiseLoadHandlersList;
   info("Apps list loaded.");
 
   registerCleanupFunction(() => {
     gBrowser.removeCurrentTab();
   });
 });
 
 add_task(async function getFeedItem() {
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   win = gBrowser.selectedBrowser.contentWindow;
 
   container = win.document.getElementById("handlersView");
   feedItem = container.querySelector("richlistitem[type='application/vnd.mozilla.maybe.feed']");
   Assert.ok(feedItem, "feedItem is present in handlersView.");
 });
 
 add_task(async function selectInternalOptionForFeed() {
@@ -79,17 +77,16 @@ add_task(async function reselectInternal
   Assert.ok(list.selectedItem,
             "Should have a selected item");
   Assert.equal(list.selectedItem.getAttribute("action"),
                Ci.nsIHandlerInfo.handleInternally,
                "Selected item should still be the same as the previously selected item.");
 });
 
 add_task(async function sortingCheck() {
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   win = gBrowser.selectedBrowser.contentWindow;
 
   const handlerView = win.document.getElementById("handlersView");
   const typeColumn = win.document.getElementById("typeColumn");
   Assert.ok(typeColumn, "typeColumn is present in handlersView.");
 
   // Test default sorting
   assertSortByType("ascending");

--- a/browser/components/preferences/in-content/tests/browser_basic_rebuild_fonts_test.js
+++ b/browser/components/preferences/in-content/tests/browser_basic_rebuild_fonts_test.js
@@ -1,21 +1,18 @@
 Services.prefs.setBoolPref("browser.preferences.instantApply", true);
 
 registerCleanupFunction(function() {
   Services.prefs.clearUserPref("browser.preferences.instantApply");
 });
 
 add_task(async function() {
   await openPreferencesViaOpenPreferencesAPI("general", { leaveOpen: true });
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   await gBrowser.contentWindow.gMainPane._selectDefaultLanguageGroupPromise;
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let contentWindow = gBrowser.contentWindow;
   var langGroup = Services.prefs.getComplexValue("font.language.group", Ci.nsIPrefLocalizedString).data;
   is(contentWindow.Preferences.get("font.language.group").value, langGroup,
      "Language group should be set correctly.");
 
   let defaultFontType = Services.prefs.getCharPref("font.default." + langGroup);
   let fontFamilyPref = "font.name." + defaultFontType + "." + langGroup;
   let fontFamily = Services.prefs.getCharPref(fontFamilyPref);

--- a/browser/components/preferences/in-content/tests/browser_bug1018066_resetScrollPosition.js
+++ b/browser/components/preferences/in-content/tests/browser_bug1018066_resetScrollPosition.js
@@ -8,18 +8,16 @@ registerCleanupFunction(function() {
     gBrowser.removeTab(gBrowser.tabs[1]);
 });
 
 add_task(async function() {
   originalWindowHeight = window.outerHeight;
   window.resizeTo(window.outerWidth, 300);
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneSearch", {leaveOpen: true});
   is(prefs.selectedPane, "paneSearch", "Search pane was selected");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let mainContent = gBrowser.contentDocument.querySelector(".main-content");
   mainContent.scrollTop = 50;
   is(mainContent.scrollTop, 50, "main-content should be scrolled 50 pixels");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   gBrowser.contentWindow.gotoPref("paneGeneral");
   is(mainContent.scrollTop, 0,
      "Switching to a different category should reset the scroll position");
 });

--- a/browser/components/preferences/in-content/tests/browser_bug1020245_openPreferences_to_paneContent.js
+++ b/browser/components/preferences/in-content/tests/browser_bug1020245_openPreferences_to_paneContent.js
@@ -1,13 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 Services.prefs.setBoolPref("browser.preferences.instantApply", true);
 
 registerCleanupFunction(function() {
   Services.prefs.clearUserPref("browser.preferences.instantApply");
 });
 
 // Test opening to the differerent panes and subcategories in Preferences
 add_task(async function() {

--- a/browser/components/preferences/in-content/tests/browser_bug1184989_prevent_scrolling_when_preferences_flipped.js
+++ b/browser/components/preferences/in-content/tests/browser_bug1184989_prevent_scrolling_when_preferences_flipped.js
@@ -4,17 +4,16 @@ const {Utils} = ChromeUtils.import("reso
 const triggeringPrincipal_base64 = Utils.SERIALIZED_SYSTEMPRINCIPAL;
 
 add_task(async function() {
   waitForExplicitFinish();
 
   const tabURL = getRootDirectory(gTestPath) + "browser_bug1184989_prevent_scrolling_when_preferences_flipped.xul";
 
   await BrowserTestUtils.withNewTab({ gBrowser, url: tabURL }, async function(browser) {
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = browser.contentDocument;
     let container = doc.getElementById("container");
 
     // Test button
     let button = doc.getElementById("button");
     button.focus();
     EventUtils.sendString(" ");
     await checkPageScrolling(container, "button");
@@ -37,17 +36,16 @@ add_task(async function() {
     // Test radio
     let radiogroup = doc.getElementById("radiogroup");
     radiogroup.focus();
     EventUtils.sendString(" ");
     await checkPageScrolling(container, "radio");
   });
 
   await BrowserTestUtils.withNewTab({ gBrowser, url: "about:preferences#search" }, async function(browser) {
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = browser.contentDocument;
     let container = doc.getElementsByClassName("main-content")[0];
 
     // Test search
     let engineList = doc.getElementById("engineList");
     engineList.focus();
     EventUtils.sendString(" ");
     is(engineList.view.selection.currentIndex, 0, "Search engineList is selected");

--- a/browser/components/preferences/in-content/tests/browser_bug410900.js
+++ b/browser/components/preferences/in-content/tests/browser_bug410900.js
@@ -17,21 +17,19 @@ function test() {
               getService(Ci.nsIExternalProtocolService);
   var info = extps.getProtocolHandlerInfo("apppanetest");
   info.possibleApplicationHandlers.appendElement(handler);
 
   var hserv = Cc["@mozilla.org/uriloader/handler-service;1"].
               getService(Ci.nsIHandlerService);
   hserv.store(info);
 
-  /* eslint-disable mozilla/no-cpows-in-tests */
   openPreferencesViaOpenPreferencesAPI("general", {leaveOpen: true})
   .then(() => gBrowser.selectedBrowser.contentWindow.promiseLoadHandlersList)
   .then(() => runTest(gBrowser.selectedBrowser.contentWindow));
-  /* eslint-enable mozilla/no-cpows-in-tests */
 }
 
 function runTest(win) {
   var rbox = win.document.getElementById("handlersView");
   ok(rbox, "handlersView is present");
 
   var items = rbox && rbox.getElementsByTagName("richlistitem");
   ok(items && items.length > 0, "App handler list populated");

--- a/browser/components/preferences/in-content/tests/browser_change_app_handler.js
+++ b/browser/components/preferences/in-content/tests/browser_change_app_handler.js
@@ -14,17 +14,16 @@ function setupFakeHandler() {
   gHandlerSvc.store(infoToModify);
 }
 
 add_task(async function() {
   setupFakeHandler();
 
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let win = gBrowser.selectedBrowser.contentWindow;
 
   let container = win.document.getElementById("handlersView");
   let ourItem = container.querySelector("richlistitem[type='text/x-test-handler']");
   ok(ourItem, "handlersView is present");
   ourItem.scrollIntoView();
   container.selectItem(ourItem);
   ok(ourItem.selected, "Should be able to select our item.");

--- a/browser/components/preferences/in-content/tests/browser_checkspelling.js
+++ b/browser/components/preferences/in-content/tests/browser_checkspelling.js
@@ -1,17 +1,16 @@
 add_task(async function() {
   SpecialPowers.pushPrefEnv({set: [
     ["layout.spellcheckDefault", 2]
   ]});
 
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let checkbox = doc.querySelector("#checkSpelling");
   is(checkbox.checked,
      Services.prefs.getIntPref("layout.spellcheckDefault") == 2,
      "checkbox should represent pref value before clicking on checkbox");
   ok(checkbox.checked, "checkbox should be checked before clicking on checkbox");
 
   checkbox.click();

--- a/browser/components/preferences/in-content/tests/browser_cookies_exceptions.js
+++ b/browser/components/preferences/in-content/tests/browser_cookies_exceptions.js
@@ -233,17 +233,16 @@ add_task(async function testSort() {
 
 async function runTest(test, observances) {
   registerCleanupFunction(function() {
     Services.prefs.clearUserPref("privacy.history.custom");
   });
 
   await openPreferencesViaOpenPreferencesAPI("panePrivacy", {leaveOpen: true});
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let historyMode = doc.getElementById("historyMode");
   historyMode.value = "custom";
   historyMode.doCommand();
 
   let promiseSubDialogLoaded =
       promiseLoadSubDialog("chrome://browser/content/preferences/permissions.xul");
   doc.getElementById("cookieExceptions").doCommand();

--- a/browser/components/preferences/in-content/tests/browser_engines.js
+++ b/browser/components/preferences/in-content/tests/browser_engines.js
@@ -1,13 +1,12 @@
 // Test Engine list
 add_task(async function() {
   let prefs = await openPreferencesViaOpenPreferencesAPI("search", {leaveOpen: true});
   is(prefs.selectedPane, "paneSearch", "Search pane is selected by default");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
 
   let tree = doc.querySelector("#engineList");
   ok(!tree.hidden, "The search engine list should be visible when Search is requested");
 
   // Check for default search engines to be displayed in the engineList
   let defaultEngines = Services.search.getDefaultEngines();
   for (let i = 0; i < defaultEngines.length; i++) {

--- a/browser/components/preferences/in-content/tests/browser_extension_controlled.js
+++ b/browser/components/preferences/in-content/tests/browser_extension_controlled.js
@@ -50,17 +50,16 @@ function waitForMutation(target, opts, c
     observer.observe(target, opts);
   });
 }
 
 function waitForMessageChange(element, cb, opts = { attributes: true, attributeFilter: ["hidden"] }) {
   return waitForMutation(element, opts, cb);
 }
 
-// eslint-disable-next-line mozilla/no-cpows-in-tests
 function getElement(id, doc = gBrowser.contentDocument) {
   return doc.getElementById(id);
 }
 
 function waitForMessageHidden(messageId, doc) {
   return waitForMessageChange(getElement(messageId, doc), target => target.hidden);
 }
 
@@ -79,17 +78,16 @@ function waitForMessageContent(messageId
   return waitForMessageChange(
     getElement(messageId, doc),
     target => target.textContent === content,
     { childList: true });
 }
 
 add_task(async function testExtensionControlledHomepage() {
   await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   is(gBrowser.currentURI.spec, "about:preferences#general",
      "#general should be in the URI for about:preferences");
   let homepagePref = () => Services.prefs.getCharPref("browser.startup.homepage");
   let originalHomepagePref = homepagePref();
   let extensionHomepage = "https://developer.mozilla.org/";
   let controlledContent = doc.getElementById("browserHomePageExtensionContent");
 
@@ -139,17 +137,16 @@ add_task(async function testExtensionCon
   await waitForMessageShown("browserHomePageExtensionContent");
   // Do the uninstall now that the enable code has been run.
   addon.uninstall();
   await BrowserTestUtils.removeTab(gBrowser.selectedTab);
 });
 
 add_task(async function testPrefLockedHomepage() {
   await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   is(gBrowser.currentURI.spec, "about:preferences#general",
      "#general should be in the URI for about:preferences");
 
   let homePagePref = "browser.startup.homepage";
   let buttonPrefs = [
     "pref.browser.homepage.disable_button.current_page",
     "pref.browser.homepage.disable_button.bookmark_page",
@@ -271,17 +268,16 @@ add_task(async function testPrefLockedHo
   is(controlledContent.hidden, true,
      "The extension controlled message is hidden when unlocked with no extension");
 
   await BrowserTestUtils.removeTab(gBrowser.selectedTab);
 });
 
 add_task(async function testExtensionControlledNewTab() {
   await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   is(gBrowser.currentURI.spec, "about:preferences#general",
      "#general should be in the URI for about:preferences");
 
   let controlledContent = doc.getElementById("browserNewTabExtensionContent");
 
   // The new tab is set to the default and message is hidden.
   ok(!aboutNewTabService.newTabURL.startsWith("moz-extension:"), "new tab is not set");
@@ -321,17 +317,16 @@ add_task(async function testExtensionCon
   // Cleanup the tab and add-on.
   await BrowserTestUtils.removeTab(gBrowser.selectedTab);
   let addon = await AddonManager.getAddonByID("@set_newtab");
   addon.uninstall();
 });
 
 add_task(async function testExtensionControlledDefaultSearch() {
   await openPreferencesViaOpenPreferencesAPI("paneSearch", {leaveOpen: true});
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let extensionId = "@set_default_search";
   let manifest = {
     manifest_version: 2,
     name: "set_default_search",
     applications: {gecko: {id: extensionId}},
     description: "set_default_search description",
     permissions: [],
@@ -417,17 +412,16 @@ add_task(async function testExtensionCon
   await originalExtension.unload();
   await updatedExtension.unload();
   await BrowserTestUtils.removeTab(gBrowser.selectedTab);
 });
 
 add_task(async function testExtensionControlledHomepageUninstalledAddon() {
   async function checkHomepageEnabled() {
     await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = gBrowser.contentDocument;
     is(gBrowser.currentURI.spec, "about:preferences#general",
       "#general should be in the URI for about:preferences");
     let controlledContent = doc.getElementById("browserHomePageExtensionContent");
 
     // The homepage is enabled.
     let homepageInut = doc.getElementById("browserHomePage");
     is(homepageInut.disabled, false, "The homepage input is enabled");
@@ -561,17 +555,16 @@ add_task(async function testExtensionCon
     let controlledMessageShown = waitForMessageShown(CONTROLLED_LABEL_ID[uiType]);
     addon.userDisabled = false;
     await controlledMessageShown;
   }
 
   let uiType = "new";
 
   await openPreferencesViaOpenPreferencesAPI("panePrivacy", {leaveOpen: true});
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
 
   is(gBrowser.currentURI.spec, "about:preferences#privacy",
    "#privacy should be in the URI for about:preferences");
 
   let controlledButton = doc.getElementById(CONTROLLED_BUTTON_ID);
 
   verifyState(false);
@@ -740,17 +733,16 @@ add_task(async function testExtensionCon
 
   async function closeProxyPanel(panelObj) {
     panelObj.panel.document.documentElement.cancelDialog();
     let panelClosingEvent = await panelObj.closingPromise;
     ok(panelClosingEvent, "Proxy panel closed.");
   }
 
   await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let mainDoc = gBrowser.contentDocument;
 
   is(gBrowser.currentURI.spec, "about:preferences#general",
    "#general should be in the URI for about:preferences");
 
   verifyState(mainDoc, false);
 
   // Open the connections panel.

--- a/browser/components/preferences/in-content/tests/browser_fluent.js
+++ b/browser/components/preferences/in-content/tests/browser_fluent.js
@@ -1,9 +1,8 @@
-/* eslint-disable mozilla/no-cpows-in-tests */
 
 function whenMainPaneLoadedFinished() {
   return new Promise(function(resolve, reject) {
     const topic = "main-pane-loaded";
     Services.obs.addObserver(function observer(aSubject) {
       Services.obs.removeObserver(observer, topic);
       resolve();
     }, topic);

--- a/browser/components/preferences/in-content/tests/browser_homepages_filter_aboutpreferences.js
+++ b/browser/components/preferences/in-content/tests/browser_homepages_filter_aboutpreferences.js
@@ -1,13 +1,12 @@
 add_task(async function testSetHomepageUseCurrent() {
   is(gBrowser.currentURI.spec, "about:blank", "Test starts with about:blank open");
   await BrowserTestUtils.openNewForegroundTab(gBrowser, "about:home");
   await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   is(gBrowser.currentURI.spec, "about:preferences#general",
      "#general should be in the URI for about:preferences");
   let oldHomepagePref = Services.prefs.getCharPref("browser.startup.homepage");
 
   let useCurrent = doc.getElementById("useCurrent");
   useCurrent.click();
 

--- a/browser/components/preferences/in-content/tests/browser_languages_subdialog.js
+++ b/browser/components/preferences/in-content/tests/browser_languages_subdialog.js
@@ -1,13 +1,11 @@
 add_task(async function() {
   await openPreferencesViaOpenPreferencesAPI("general", { leaveOpen: true });
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   const contentDocument = gBrowser.contentDocument;
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   const dialogOverlay = content.gSubDialog._preloadDialog._overlay;
 
   async function languagesSubdialogOpened() {
     const promiseSubDialogLoaded = promiseLoadSubDialog("chrome://browser/content/preferences/languages.xul");
     contentDocument.getElementById("chooseLanguage").click();
     const win = await promiseSubDialogLoaded;
     win.Preferences.forceEnableInstantApply();
     is(dialogOverlay.style.visibility, "visible", "The dialog is visible.");

--- a/browser/components/preferences/in-content/tests/browser_layersacceleration.js
+++ b/browser/components/preferences/in-content/tests/browser_layersacceleration.js
@@ -2,17 +2,16 @@ add_task(async function() {
   SpecialPowers.pushPrefEnv({set: [
     ["gfx.direct2d.disabled", false],
     ["layers.acceleration.disabled", false]
   ]});
 
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let checkbox = doc.querySelector("#allowHWAccel");
   is(!checkbox.checked,
      Services.prefs.getBoolPref("layers.acceleration.disabled"),
      "checkbox should represent inverted pref value before clicking on checkbox");
 
   checkbox.click();
 

--- a/browser/components/preferences/in-content/tests/browser_masterpassword.js
+++ b/browser/components/preferences/in-content/tests/browser_masterpassword.js
@@ -1,13 +1,12 @@
 add_task(async function() {
   let prefs = await openPreferencesViaOpenPreferencesAPI("panePrivacy", {leaveOpen: true});
   is(prefs.selectedPane, "panePrivacy", "Privacy pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   // Fake the subdialog and LoginHelper
   let win = doc.defaultView;
   let dialogURL = "";
   win.gSubDialog = {
     open(aDialogURL, unused, unused2, aCallback) {
       dialogURL = aDialogURL;
       masterPasswordSet = masterPasswordNextState;

--- a/browser/components/preferences/in-content/tests/browser_notifications_do_not_disturb.js
+++ b/browser/components/preferences/in-content/tests/browser_notifications_do_not_disturb.js
@@ -6,17 +6,16 @@ registerCleanupFunction(function() {
   while (gBrowser.tabs[1])
     gBrowser.removeTab(gBrowser.tabs[1]);
 });
 
 add_task(async function() {
   let prefs = await openPreferencesViaOpenPreferencesAPI("panePrivacy", {leaveOpen: true});
   is(prefs.selectedPane, "panePrivacy", "Privacy pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let notificationsDoNotDisturbBox = doc.getElementById("notificationsDoNotDisturbBox");
   if (notificationsDoNotDisturbBox.hidden) {
     todo(false, "Do not disturb is not available on this platform");
     return;
   }
 
   let alertService;

--- a/browser/components/preferences/in-content/tests/browser_password_management.js
+++ b/browser/components/preferences/in-content/tests/browser_password_management.js
@@ -61,12 +61,11 @@ add_task(async function test_deletePassw
   if (AppConstants.platform == "macosx") {
     EventUtils.synthesizeKey("KEY_Backspace");
   } else {
     EventUtils.synthesizeKey("KEY_Delete");
   }
 
   await TestUtils.waitForCondition(() => tree.view.rowCount == 0);
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   is_element_visible(content.gSubDialog._dialogs[0]._box,
     "Subdialog is visible after deleting an element");
 });

--- a/browser/components/preferences/in-content/tests/browser_performance.js
+++ b/browser/components/preferences/in-content/tests/browser_performance.js
@@ -8,17 +8,16 @@ add_task(async function() {
     ["browser.preferences.defaultPerformanceSettings.enabled", true],
   ]});
 });
 
 add_task(async function() {
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let useRecommendedPerformanceSettings = doc.querySelector("#useRecommendedPerformanceSettings");
 
   is(Services.prefs.getBoolPref("browser.preferences.defaultPerformanceSettings.enabled"), true,
     "pref value should be true before clicking on checkbox");
   ok(useRecommendedPerformanceSettings.checked, "checkbox should be checked before clicking on checkbox");
 
   useRecommendedPerformanceSettings.click();
@@ -74,17 +73,16 @@ add_task(async function() {
   Services.prefs.setBoolPref("browser.preferences.defaultPerformanceSettings.enabled", true);
   await BrowserTestUtils.removeTab(gBrowser.selectedTab);
 });
 
 add_task(async function() {
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let useRecommendedPerformanceSettings = doc.querySelector("#useRecommendedPerformanceSettings");
   let allowHWAccel = doc.querySelector("#allowHWAccel");
   let contentProcessCount = doc.querySelector("#contentProcessCount");
   let performanceSettings = doc.querySelector("#performanceSettings");
 
   useRecommendedPerformanceSettings.click();
   allowHWAccel.click();
@@ -100,17 +98,16 @@ add_task(async function() {
   Services.prefs.setBoolPref("browser.preferences.defaultPerformanceSettings.enabled", true);
   await BrowserTestUtils.removeTab(gBrowser.selectedTab);
 });
 
 add_task(async function() {
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let performanceSettings = doc.querySelector("#performanceSettings");
 
   is(performanceSettings.hidden, true, "performance settings section should not be shown");
 
   Services.prefs.setBoolPref("browser.preferences.defaultPerformanceSettings.enabled", false);
 
   is(performanceSettings.hidden, false, "performance settings section should be shown");
@@ -120,17 +117,16 @@ add_task(async function() {
 });
 
 add_task(async function() {
   Services.prefs.setIntPref("dom.ipc.processCount", 7);
 
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
 
   let performanceSettings = doc.querySelector("#performanceSettings");
   is(performanceSettings.hidden, false, "performance settings section should be shown");
 
   let contentProcessCount = doc.querySelector("#contentProcessCount");
   is(Services.prefs.getIntPref("dom.ipc.processCount"), 7, "pref value should be 7");
   is(contentProcessCount.selectedItem.value, 7, "selected item should be 7");
@@ -140,17 +136,16 @@ add_task(async function() {
 });
 
 add_task(async function() {
   Services.prefs.setBoolPref("layers.acceleration.disabled", true);
 
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
 
   let performanceSettings = doc.querySelector("#performanceSettings");
   is(performanceSettings.hidden, false, "performance settings section should be shown");
 
   let allowHWAccel = doc.querySelector("#allowHWAccel");
   is(Services.prefs.getBoolPref("layers.acceleration.disabled"), true,
     "pref value is false");

--- a/browser/components/preferences/in-content/tests/browser_performance_e10srollout.js
+++ b/browser/components/preferences/in-content/tests/browser_performance_e10srollout.js
@@ -11,17 +11,16 @@ add_task(async function() {
 
 add_task(async function testPrefsAreDefault() {
   Services.prefs.setIntPref("dom.ipc.processCount", DEFAULT_PROCESS_COUNT);
   Services.prefs.setBoolPref("browser.preferences.defaultPerformanceSettings.enabled", true);
 
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let useRecommendedPerformanceSettings = doc.querySelector("#useRecommendedPerformanceSettings");
 
   is(Services.prefs.getBoolPref("browser.preferences.defaultPerformanceSettings.enabled"), true,
      "pref value should be true before clicking on checkbox");
   ok(useRecommendedPerformanceSettings.checked, "checkbox should be checked before clicking on checkbox");
 
   useRecommendedPerformanceSettings.click();
@@ -46,17 +45,16 @@ add_task(async function testPrefsAreDefa
 
 add_task(async function testPrefsSetByUser() {
   Services.prefs.setIntPref("dom.ipc.processCount", DEFAULT_PROCESS_COUNT + 2);
   Services.prefs.setBoolPref("browser.preferences.defaultPerformanceSettings.enabled", false);
 
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let performanceSettings = doc.querySelector("#performanceSettings");
   is(performanceSettings.hidden, false, "performance settings section is shown");
 
   let contentProcessCount = doc.querySelector("#contentProcessCount");
   is(contentProcessCount.disabled, false, "process count control should be enabled");
   is(Services.prefs.getIntPref("dom.ipc.processCount"), DEFAULT_PROCESS_COUNT + 2, "process count should be the set value");
   is(contentProcessCount.selectedItem.value, DEFAULT_PROCESS_COUNT + 2, "selected item should be the set one");

--- a/browser/components/preferences/in-content/tests/browser_performance_non_e10s.js
+++ b/browser/components/preferences/in-content/tests/browser_performance_non_e10s.js
@@ -8,17 +8,16 @@ add_task(async function() {
     ["browser.preferences.defaultPerformanceSettings.enabled", true],
   ]});
 });
 
 add_task(async function() {
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let useRecommendedPerformanceSettings = doc.querySelector("#useRecommendedPerformanceSettings");
 
   is(Services.prefs.getBoolPref("browser.preferences.defaultPerformanceSettings.enabled"), true,
     "pref value should be true before clicking on checkbox");
   ok(useRecommendedPerformanceSettings.checked, "checkbox should be checked before clicking on checkbox");
 
   useRecommendedPerformanceSettings.click();
@@ -62,17 +61,16 @@ add_task(async function() {
   Services.prefs.setBoolPref("browser.preferences.defaultPerformanceSettings.enabled", true);
   await BrowserTestUtils.removeTab(gBrowser.selectedTab);
 });
 
 add_task(async function() {
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
   let performanceSettings = doc.querySelector("#performanceSettings");
 
   is(performanceSettings.hidden, true, "performance settings section should not be shown");
 
   Services.prefs.setBoolPref("browser.preferences.defaultPerformanceSettings.enabled", false);
 
   is(performanceSettings.hidden, false, "performance settings section should be shown");
@@ -82,17 +80,16 @@ add_task(async function() {
 });
 
 add_task(async function() {
   Services.prefs.setBoolPref("layers.acceleration.disabled", true);
 
   let prefs = await openPreferencesViaOpenPreferencesAPI("paneGeneral", {leaveOpen: true});
   is(prefs.selectedPane, "paneGeneral", "General pane was selected");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocument;
 
   let performanceSettings = doc.querySelector("#performanceSettings");
   is(performanceSettings.hidden, false, "performance settings section should be shown");
 
   let allowHWAccel = doc.querySelector("#allowHWAccel");
   is(Services.prefs.getBoolPref("layers.acceleration.disabled"), true,
     "pref value is false");

--- a/browser/components/preferences/in-content/tests/browser_permissions_urlFieldHidden.js
+++ b/browser/components/preferences/in-content/tests/browser_permissions_urlFieldHidden.js
@@ -1,15 +1,14 @@
 "use strict";
 
 const PERMISSIONS_URL = "chrome://browser/content/preferences/permissions.xul";
 
 add_task(async function urlFieldVisibleForPopupPermissions(finish) {
   await openPreferencesViaOpenPreferencesAPI("panePrivacy", {leaveOpen: true});
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let win = gBrowser.selectedBrowser.contentWindow;
   let doc = win.document;
   let popupPolicyCheckbox = doc.getElementById("popupPolicy");
   ok(!popupPolicyCheckbox.checked, "popupPolicyCheckbox should be unchecked by default");
   popupPolicyCheckbox.click();
   let popupPolicyButton = doc.getElementById("popupPolicyButton");
   ok(popupPolicyButton, "popupPolicyButton found");
   let dialogPromise = promiseLoadSubDialog(PERMISSIONS_URL);

--- a/browser/components/preferences/in-content/tests/browser_privacypane.js
+++ b/browser/components/preferences/in-content/tests/browser_privacypane.js
@@ -1,13 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 // Test the initial value of Browser Error collection checkbox
 add_task(async function testBrowserErrorInitialValue() {
   // Skip if non-Nightly since the checkbox will be missing.
   if (!AppConstants.NIGHTLY_BUILD) {
     return;
   }
 
   await SpecialPowers.pushPrefEnv({

--- a/browser/components/preferences/in-content/tests/browser_sanitizeOnShutdown_prefLocked.js
+++ b/browser/components/preferences/in-content/tests/browser_sanitizeOnShutdown_prefLocked.js
@@ -3,17 +3,16 @@
 function switchToCustomHistoryMode(doc) {
   // Select the last item in the menulist.
   let menulist = doc.getElementById("historyMode");
   menulist.focus();
   EventUtils.sendKey("UP");
 }
 
 function testPrefStateMatchesLockedState() {
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let win = gBrowser.contentWindow;
   let doc = win.document;
   switchToCustomHistoryMode(doc);
 
   let checkbox = doc.getElementById("alwaysClear");
   let preference = win.Preferences.get("privacy.sanitize.sanitizeOnShutdown");
   is(checkbox.disabled, preference.locked, "Always Clear checkbox should be enabled when preference is not locked.");
 

--- a/browser/components/preferences/in-content/tests/browser_search_within_preferences_1.js
+++ b/browser/components/preferences/in-content/tests/browser_search_within_preferences_1.js
@@ -1,15 +1,13 @@
 "use strict";
 /**
  * This file contains tests for the Preferences search bar.
  */
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 requestLongerTimeout(6);
 
 /**
  * Tests to see if search bar is being shown when pref is turned on
  */
 add_task(async function() {
   await openPreferencesViaOpenPreferencesAPI("paneGeneral", { leaveOpen: true });
   let searchInput = gBrowser.contentDocument.getElementById("searchInput");

--- a/browser/components/preferences/in-content/tests/browser_search_within_preferences_2.js
+++ b/browser/components/preferences/in-content/tests/browser_search_within_preferences_2.js
@@ -1,15 +1,13 @@
 "use strict";
 /**
  * This file contains tests for the Preferences search bar.
  */
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 /**
  * Enabling searching functionality. Will display search bar from this testcase forward.
  */
 add_task(async function() {
   await SpecialPowers.pushPrefEnv({"set": [["browser.preferences.search", true]]});
 });
 
 /**

--- a/browser/components/preferences/in-content/tests/browser_search_within_preferences_command.js
+++ b/browser/components/preferences/in-content/tests/browser_search_within_preferences_command.js
@@ -1,12 +1,10 @@
 "use strict";
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 /**
  * Test for "command" event on search input (when user clicks the x button)
  */
 add_task(async function() {
   await SpecialPowers.pushPrefEnv({"set": [["browser.storageManager.enabled", false]]});
   await openPreferencesViaOpenPreferencesAPI("privacy", {leaveOpen: true});
   let generalPane = gBrowser.contentDocument.getElementById("generalCategory");
 

--- a/browser/components/preferences/in-content/tests/browser_security-1.js
+++ b/browser/components/preferences/in-content/tests/browser_security-1.js
@@ -43,17 +43,16 @@ add_task(async function() {
     is(blockDownloads.hasAttribute("disabled"), !checked, "block downloads checkbox is set correctly");
 
     is(checked, val1 && val2, "safebrowsing preference is initialized correctly");
     // should be disabled when checked is false (= pref is turned off)
     is(blockUncommon.hasAttribute("disabled"), !checked, "block uncommon checkbox is set correctly");
 
     // scroll the checkbox into the viewport and click checkbox
     checkbox.scrollIntoView();
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     EventUtils.synthesizeMouseAtCenter(checkbox, {}, gBrowser.selectedBrowser.contentWindow);
 
     // check that both settings are now turned on or off
     is(Services.prefs.getBoolPref("browser.safebrowsing.phishing.enabled"), !checked,
        "safebrowsing.enabled is set correctly");
     is(Services.prefs.getBoolPref("browser.safebrowsing.malware.enabled"), !checked,
        "safebrowsing.malware.enabled is set correctly");
 

--- a/browser/components/preferences/in-content/tests/browser_security-2.js
+++ b/browser/components/preferences/in-content/tests/browser_security-2.js
@@ -40,17 +40,16 @@ add_task(async function() {
     let blockUncommon = doc.getElementById("blockUncommonUnwanted");
     let checked = checkbox.checked;
     is(checked, val, "downloads preference is initialized correctly");
     // should be disabled when val is false (= pref is turned off)
     is(blockUncommon.hasAttribute("disabled"), !val, "block uncommon checkbox is set correctly");
 
     // scroll the checkbox into view, otherwise the synthesizeMouseAtCenter will be ignored, and click it
     checkbox.scrollIntoView();
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     EventUtils.synthesizeMouseAtCenter(checkbox, {}, gBrowser.selectedBrowser.contentWindow);
 
     // check that setting is now turned on or off
     is(Services.prefs.getBoolPref("browser.safebrowsing.downloads.enabled"), !checked,
        "safebrowsing.downloads preference is set correctly");
 
     // check if the uncommon warning checkbox has updated
     is(blockUncommon.hasAttribute("disabled"), val, "block uncommon checkbox is set correctly");
@@ -80,17 +79,16 @@ add_task(async function() {
 
     let doc = gBrowser.selectedBrowser.contentDocument;
     let checkbox = doc.getElementById("blockUncommonUnwanted");
     let checked = checkbox.checked;
     is(checked, val1 && val2, "unwanted/uncommon preference is initialized correctly");
 
     // scroll the checkbox into view, otherwise the synthesizeMouseAtCenter will be ignored, and click it
     checkbox.scrollIntoView();
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     EventUtils.synthesizeMouseAtCenter(checkbox, {}, gBrowser.selectedBrowser.contentWindow);
 
     // check that both settings are now turned on or off
     is(Services.prefs.getBoolPref("browser.safebrowsing.downloads.remote.block_potentially_unwanted"), !checked,
        "block_potentially_unwanted is set correctly");
     is(Services.prefs.getBoolPref("browser.safebrowsing.downloads.remote.block_uncommon"), !checked,
        "block_uncommon is set correctly");
 

--- a/browser/components/preferences/in-content/tests/browser_siteData.js
+++ b/browser/components/preferences/in-content/tests/browser_siteData.js
@@ -37,17 +37,16 @@ add_task(async function() {
   await BrowserTestUtils.waitForContentEvent(
     gBrowser.selectedBrowser, "test-indexedDB-done", false, null, true);
   await BrowserTestUtils.removeTab(gBrowser.selectedTab);
 
   let updatedPromise = promiseSiteDataManagerSitesUpdated();
   await openPreferencesViaOpenPreferencesAPI("privacy", { leaveOpen: true });
   await updatedPromise;
   await openSiteDataSettingsDialog();
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let dialog = content.gSubDialog._topDialog;
   let dialogFrame = dialog._frame;
   let frameDoc = dialogFrame.contentDocument;
 
   let siteItems = frameDoc.getElementsByTagName("richlistitem");
   is(siteItems.length, 2, "Should list sites using quota usage or appcache");
 
   let appcacheSite = frameDoc.querySelector(`richlistitem[host="${TEST_OFFLINE_HOST}"]`);

--- a/browser/components/preferences/in-content/tests/browser_siteData2.js
+++ b/browser/components/preferences/in-content/tests/browser_siteData2.js
@@ -1,14 +1,12 @@
 "use strict";
 const { SiteDataManager } = ChromeUtils.import("resource:///modules/SiteDataManager.jsm", {});
 const REMOVE_DIALOG_URL = "chrome://browser/content/preferences/siteDataRemoveSelected.xul";
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 function promiseSettingsDialogClose() {
   return new Promise(resolve => {
     let win = gBrowser.selectedBrowser.contentWindow;
     let dialogOverlay = win.gSubDialog._topDialog._overlay;
     let dialogWin = win.gSubDialog._topDialog._frame.contentWindow;
     dialogWin.addEventListener("unload", function unload() {
       if (dialogWin.document.documentURI === "chrome://browser/content/preferences/siteDataSettings.xul") {
         isnot(dialogOverlay.style.visibility, "visible", "The Settings dialog should be hidden");

--- a/browser/components/preferences/in-content/tests/browser_siteData3.js
+++ b/browser/components/preferences/in-content/tests/browser_siteData3.js
@@ -76,17 +76,16 @@ add_task(async function() {
       persisted: false
     },
   ]);
 
   let updatedPromise = promiseSiteDataManagerSitesUpdated();
   await openPreferencesViaOpenPreferencesAPI("privacy", { leaveOpen: true });
   await updatedPromise;
   await openSiteDataSettingsDialog();
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let win = gBrowser.selectedBrowser.contentWindow;
   let dialogFrame = win.gSubDialog._topDialog._frame;
   let frameDoc = dialogFrame.contentDocument;
 
   let siteItems = frameDoc.getElementsByTagName("richlistitem");
   is(siteItems.length, 1, "Should group sites across scheme, port and origin attributes");
 
   let columns = siteItems[0].querySelectorAll(".item-box > label");
@@ -129,17 +128,16 @@ add_task(async function() {
     },
   ]);
 
   let updatePromise = promiseSiteDataManagerSitesUpdated();
   await openPreferencesViaOpenPreferencesAPI("privacy", { leaveOpen: true });
   await updatePromise;
   await openSiteDataSettingsDialog();
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let dialog = content.gSubDialog._topDialog;
   let dialogFrame = dialog._frame;
   let frameDoc = dialogFrame.contentDocument;
   let hostCol = frameDoc.getElementById("hostCol");
   let usageCol = frameDoc.getElementById("usageCol");
   let cookiesCol = frameDoc.getElementById("cookiesCol");
   let sitesList = frameDoc.getElementById("sitesList");
 
@@ -244,17 +242,16 @@ add_task(async function() {
     },
   ]);
 
   let updatePromise = promiseSiteDataManagerSitesUpdated();
   await openPreferencesViaOpenPreferencesAPI("privacy", { leaveOpen: true });
   await updatePromise;
   await openSiteDataSettingsDialog();
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let dialog = content.gSubDialog._topDialog;
   let dialogFrame = dialog._frame;
   let frameDoc = dialogFrame.contentDocument;
   let lastAccessedCol = frameDoc.getElementById("lastAccessedCol");
   let sitesList = frameDoc.getElementById("sitesList");
 
   // Test sorting on the date column
   lastAccessedCol.click();

--- a/browser/components/preferences/in-content/tests/browser_site_login_exceptions.js
+++ b/browser/components/preferences/in-content/tests/browser_site_login_exceptions.js
@@ -66,12 +66,11 @@ add_task(async function deleteALoginExce
   if (AppConstants.platform == "macosx") {
     EventUtils.synthesizeKey("KEY_Backspace");
   } else {
     EventUtils.synthesizeKey("KEY_Delete");
   }
 
   await TestUtils.waitForCondition(() => tree.view.rowCount == 0);
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   is_element_visible(content.gSubDialog._dialogs[0]._box,
     "Subdialog is visible after deleting an element");
 });

--- a/browser/components/preferences/in-content/tests/browser_spotlight.js
+++ b/browser/components/preferences/in-content/tests/browser_spotlight.js
@@ -1,9 +1,8 @@
-/* eslint-disable mozilla/no-cpows-in-tests */
 
 add_task(async function test_reports_section() {
   let prefs = await openPreferencesViaOpenPreferencesAPI("privacy-reports", {leaveOpen: true});
   is(prefs.selectedPane, "panePrivacy", "Privacy pane is selected by default");
   let doc = gBrowser.contentDocument;
   is(doc.location.hash, "#privacy", "The subcategory should be removed from the URI");
   await TestUtils.waitForCondition(() => doc.querySelector(".spotlight"),
     "Wait for the reports section is spotlighted.");

--- a/browser/components/preferences/in-content/tests/browser_subdialogs.js
+++ b/browser/components/preferences/in-content/tests/browser_subdialogs.js
@@ -180,17 +180,16 @@ add_task(async function check_reopening_
   await close_subdialog_and_test_generic_end_state(tab.linkedBrowser,
     function() { content.window.gSubDialog._topDialog._frame.contentDocument.documentElement.acceptDialog(); },
     "accept", 1);
 });
 
 add_task(async function check_opening_while_closing() {
   await open_subdialog_and_test_generic_start_state(tab.linkedBrowser);
   info("closing");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   content.window.gSubDialog._topDialog.close();
   info("reopening immediately after calling .close()");
   await open_subdialog_and_test_generic_start_state(tab.linkedBrowser);
   await close_subdialog_and_test_generic_end_state(tab.linkedBrowser,
     function() { content.window.gSubDialog._topDialog._frame.contentDocument.documentElement.acceptDialog(); },
     "accept", 1);
 
 });

--- a/browser/components/search/test/browser_aboutSearchReset.js
+++ b/browser/components/search/test/browser_aboutSearchReset.js
@@ -59,17 +59,16 @@ var gTests = [
                       uri.spec;
 
     let rawEngine = engine.wrappedJSObject;
     let initialHash = rawEngine.getAttr("loadPathHash");
     rawEngine.setAttr("loadPathHash", "broken");
     Services.prefs.setCharPref(kStatusPref, "pending");
 
     let loadPromise = promiseStoppedLoad(expectedURL);
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     gBrowser.contentDocumentAsCPOW.getElementById("searchResetKeepCurrent").click();
     await loadPromise;
 
     is(engine, Services.search.currentEngine,
        "the custom engine is still default");
     is(rawEngine.getAttr("loadPathHash"), initialHash,
        "the loadPathHash has been fixed");
 
@@ -78,17 +77,16 @@ var gTests = [
   }
 },
 
 {
   desc: "Test the 'Restore Search Defaults' button.",
   async run() {
     let currentEngine = Services.search.currentEngine;
     let originalEngine = Services.search.originalDefaultEngine;
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let doc = gBrowser.contentDocumentAsCPOW;
     let defaultEngineSpan = doc.getElementById("defaultEngine");
     is(defaultEngineSpan.textContent, originalEngine.name,
        "the name of the original default engine is displayed");
 
     let expectedURL = originalEngine.
                       getSubmission(kSearchStr, null, kSearchPurpose).
                       uri.spec;
@@ -111,17 +109,16 @@ var gTests = [
 
 {
   desc: "Click the settings link.",
   async run() {
     Services.prefs.setCharPref(kStatusPref, "pending");
     let loadPromise = BrowserTestUtils.browserLoaded(gBrowser.selectedBrowser,
                                                      false,
                                                      "about:preferences#search");
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     gBrowser.contentDocumentAsCPOW.getElementById("linkSettingsPage").click();
     await loadPromise;
 
     checkTelemetryRecords(TELEMETRY_RESULT_ENUM.OPENED_SETTINGS);
     is(Services.prefs.getCharPref(kStatusPref), "customized");
   }
 },
 

--- a/browser/components/search/test/browser_abouthome_behavior.js
+++ b/browser/components/search/test/browser_abouthome_behavior.js
@@ -34,17 +34,16 @@ function test() {
       if (event.originalTarget != tab.linkedBrowser.contentDocumentAsCPOW ||
           event.target.location.href == "about:blank") {
         info("skipping spurious load event");
         return;
       }
       tab.linkedBrowser.removeEventListener("load", load, true);
 
       // Observe page setup
-      // eslint-disable-next-line mozilla/no-cpows-in-tests
       let doc = gBrowser.contentDocumentAsCPOW;
       gMutationObserver = new MutationObserver(function(mutations) {
         for (let mutation of mutations) {
           if (mutation.attributeName == "searchEngineName") {
             // Re-add the listener, and perform a search
             gBrowser.addProgressListener(listener);
             gMutationObserver.disconnect();
             gMutationObserver = null;

--- a/browser/components/sessionstore/test/browser_480893.js
+++ b/browser/components/sessionstore/test/browser_480893.js
@@ -11,17 +11,16 @@ add_task(async function() {
     ]
   });
 
   let tab = BrowserTestUtils.addTab(gBrowser, "about:sessionrestore");
   gBrowser.selectedTab = tab;
   let browser = tab.linkedBrowser;
   await BrowserTestUtils.browserLoaded(browser, false, "about:sessionrestore");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = browser.contentDocument;
 
   // Click on the "Close" button after about:sessionrestore is loaded.
   doc.getElementById("errorCancel").click();
 
   await BrowserTestUtils.browserLoaded(browser, false, "about:blank");
 
   // Test that starting a new session loads the homepage (set to http://mochi.test:8888)
@@ -31,17 +30,16 @@ add_task(async function() {
     "set": [
       ["browser.startup.homepage", homepage],
       ["browser.startup.page", 1],
     ]
   });
 
   browser.loadURI("about:sessionrestore");
   await BrowserTestUtils.browserLoaded(browser, false, "about:sessionrestore");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   doc = browser.contentDocument;
 
   // Click on the "Close" button after about:sessionrestore is loaded.
   doc.getElementById("errorCancel").click();
   await BrowserTestUtils.browserLoaded(browser);
 
   is(browser.currentURI.spec, homepage, "loaded page is the homepage");
 

--- a/browser/components/sessionstore/test/browser_590563.js
+++ b/browser/components/sessionstore/test/browser_590563.js
@@ -27,25 +27,23 @@ function test() {
         middleClickTest(win);
       }, win);
     });
   });
 }
 
 async function middleClickTest(win) {
   let browser = win.gBrowser.selectedBrowser;
-  /* eslint-disable mozilla/no-cpows-in-tests */
   let tabsToggle = browser.contentDocument.getElementById("tabsToggle");
   EventUtils.synthesizeMouseAtCenter(tabsToggle, { button: 0 }, browser.contentWindow);
   let treeContainer = browser.contentDocument.querySelector(".tree-container");
   await BrowserTestUtils.waitForCondition(() => win.getComputedStyle(treeContainer).visibility == "visible");
 
   let tree = browser.contentDocument.getElementById("tabList");
   is(tree.view.rowCount, 3, "There should be three items");
-  /* eslint-enable mozilla/no-cpows-in-tests */
 
   // click on the first tab item
   var rect = tree.treeBoxObject.getCoordsForCellItem(1, tree.columns[1], "text");
   EventUtils.synthesizeMouse(tree.body, rect.x, rect.y, { button: 1 },
                              browser.contentWindow);
   // click on the second tab item
   rect = tree.treeBoxObject.getCoordsForCellItem(2, tree.columns[1], "text");
   EventUtils.synthesizeMouse(tree.body, rect.x, rect.y, { button: 1 },

--- a/browser/components/sessionstore/test/browser_705597.js
+++ b/browser/components/sessionstore/test/browser_705597.js
@@ -42,17 +42,16 @@ function test() {
           waitForBrowserState(blankState, finish);
         });
 
         // Force reload the browser to deprecate the subframes.
         browser.reloadWithFlags(Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE);
       });
 
       // Create a dynamic subframe.
-      // eslint-disable-next-line mozilla/no-cpows-in-tests
       let doc = browser.contentDocument;
       let iframe = doc.createElement("iframe");
       doc.body.appendChild(iframe);
       iframe.setAttribute("src", "about:mozilla");
     });
   });
 }
 

--- a/browser/components/sessionstore/test/browser_707862.js
+++ b/browser/components/sessionstore/test/browser_707862.js
@@ -41,17 +41,16 @@ function test() {
           });
         });
 
         // Force reload the browser to deprecate the subframes.
         browser.reloadWithFlags(Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE);
       });
 
       // Create a dynamic subframe.
-      // eslint-disable-next-line mozilla/no-cpows-in-tests
       let doc = browser.contentDocument;
       let iframe = doc.createElement("iframe");
       doc.body.appendChild(iframe);
       iframe.setAttribute("src", "about:mozilla");
     });
   });
 
   // This test relies on the test timing out in order to indicate failure so

--- a/browser/components/sessionstore/test/browser_aboutSessionRestore.js
+++ b/browser/components/sessionstore/test/browser_aboutSessionRestore.js
@@ -24,17 +24,16 @@ add_task(async function() {
   await promiseBrowserLoaded(browser);
 
   // Fake a post-crash tab.
   ss.setTabState(tab, JSON.stringify(TAB_STATE));
   await promiseTabRestored(tab);
 
   ok(gBrowser.tabs.length > 1, "we have more than one tab");
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let view = browser.contentDocument.getElementById("tabList").view;
   ok(view.isContainer(0), "first entry is the window");
   is(view.getCellProperties(1, { id: "title" }), "icon",
     "second entry is the tab and has a favicon");
 
   browser.messageManager.loadFrameScript(FRAME_SCRIPT, true);
 
   // Wait until the new window was restored.

--- a/browser/components/sessionstore/test/browser_crashedTabs.js
+++ b/browser/components/sessionstore/test/browser_crashedTabs.js
@@ -385,17 +385,16 @@ add_task(async function test_hide_restor
   browser.loadURI(PAGE_1);
   await promiseBrowserLoaded(browser);
 
   await TabStateFlusher.flush(browser);
 
   // Crash the tab
   await BrowserTestUtils.crashBrowser(browser);
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = browser.contentDocument;
   let restoreAllButton = doc.getElementById("restoreAll");
   let restoreOneButton = doc.getElementById("restoreTab");
 
   let restoreAllStyles = window.getComputedStyle(restoreAllButton);
   is(restoreAllStyles.display, "none", "Restore All button should be hidden");
   ok(restoreOneButton.classList.contains("primary"), "Restore Tab button should have the primary class");
 
@@ -416,17 +415,16 @@ add_task(async function test_hide_restor
   // sending its AboutTabCrashedReady event before we know for
   // sure whether or not we're showing the right Restore buttons.
   let otherBrowserReady = promiseTabCrashedReady(otherWinBrowser);
 
   // Crash the first tab.
   await BrowserTestUtils.crashBrowser(browser);
   await otherBrowserReady;
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   doc = browser.contentDocument;
   restoreAllButton = doc.getElementById("restoreAll");
   restoreOneButton = doc.getElementById("restoreTab");
 
   restoreAllStyles = window.getComputedStyle(restoreAllButton);
   isnot(restoreAllStyles.display, "none", "Restore All button should not be hidden");
   ok(!(restoreOneButton.classList.contains("primary")), "Restore Tab button should not have the primary class");
 

--- a/browser/components/sessionstore/test/browser_swapDocShells.js
+++ b/browser/components/sessionstore/test/browser_swapDocShells.js
@@ -21,16 +21,15 @@ function promiseDelayedStartupFinished(w
   return new Promise(resolve => {
     whenDelayedStartupFinished(win, resolve);
   });
 }
 
 function promiseBrowserHasURL(browser, url) {
   let promise = Promise.resolve();
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   if (browser.contentDocument.readyState === "complete" &&
       browser.currentURI.spec === url) {
     return promise;
   }
 
   return promise.then(() => promiseBrowserHasURL(browser, url));
 }

--- a/browser/components/shell/test/browser_1119088.js
+++ b/browser/components/shell/test/browser_1119088.js
@@ -27,17 +27,16 @@ function onPageLoad() {
   wpFile.append("logo.png");
   if (wpFile.exists()) {
     wpFile.remove(false);
   }
 
   let shell = Cc["@mozilla.org/browser/shell-service;1"].
               getService(Ci.nsIShellService);
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let image = gBrowser.contentDocumentAsCPOW.images[0];
   shell.setDesktopBackground(image, 0, "logo.png");
 
   setTimeout(function() {
     ok(wpFile.exists(), "Desktop background was written to disk.");
 
     desktopBackgroundDbBackup.moveTo(null, desktopBackgroundDb.leafName);
     wpFile.remove(false);

--- a/browser/extensions/onboarding/test/browser/browser_onboarding_skip_tour.js
+++ b/browser/extensions/onboarding/test/browser/browser_onboarding_skip_tour.js
@@ -31,13 +31,12 @@ add_task(async function test_hide_skip_b
   resetOnboardingDefaultState();
   Preferences.set("browser.onboarding.skip-tour-button.hide", true);
 
   let tab = await openTab(ABOUT_NEWTAB_URL);
   await promiseOnboardingOverlayLoaded(tab.linkedBrowser);
   await BrowserTestUtils.synthesizeMouseAtCenter("#onboarding-overlay-button", {}, tab.linkedBrowser);
   await promiseOnboardingOverlayOpened(tab.linkedBrowser);
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   ok(!gBrowser.contentDocumentAsCPOW.querySelector("#onboarding-skip-tour-button"), "should not render the skip button");
 
   await BrowserTestUtils.removeTab(tab);
 });

--- a/browser/extensions/onboarding/test/browser/browser_onboarding_tourset.js
+++ b/browser/extensions/onboarding/test/browser/browser_onboarding_tourset.js
@@ -8,17 +8,16 @@ requestLongerTimeout(2);
 add_task(async function test_onboarding_default_new_tourset() {
   resetOnboardingDefaultState();
 
   let tab = await openTab(ABOUT_NEWTAB_URL);
   await promiseOnboardingOverlayLoaded(tab.linkedBrowser);
   await BrowserTestUtils.synthesizeMouseAtCenter("#onboarding-overlay-button", {}, tab.linkedBrowser);
   await promiseOnboardingOverlayOpened(tab.linkedBrowser);
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocumentAsCPOW;
   let doms = doc.querySelectorAll(".onboarding-tour-item");
   is(doms.length, TOUR_IDs.length, "has exact tour numbers");
   doms.forEach((dom, idx) => {
     is(TOUR_IDs[idx], dom.id, "contain defined onboarding id");
   });
 
   await BrowserTestUtils.removeTab(tab);
@@ -39,17 +38,16 @@ add_task(async function test_onboarding_
     ["browser.onboarding.newtour", "private,addons,customize"],
   ]});
 
   let tab = await openTab(ABOUT_NEWTAB_URL);
   await promiseOnboardingOverlayLoaded(tab.linkedBrowser);
   await BrowserTestUtils.synthesizeMouseAtCenter("#onboarding-overlay-button", {}, tab.linkedBrowser);
   await promiseOnboardingOverlayOpened(tab.linkedBrowser);
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocumentAsCPOW;
   let doms = doc.querySelectorAll(".onboarding-tour-item");
   is(doms.length, CUSTOM_NEW_TOURs.length, "has exact tour numbers");
   doms.forEach((dom, idx) => {
     is(CUSTOM_NEW_TOURs[idx], dom.id, "contain defined onboarding id");
   });
 
   await BrowserTestUtils.removeTab(tab);
@@ -69,17 +67,16 @@ add_task(async function test_onboarding_
     ["browser.onboarding.updatetour", "customize,private,addons"],
   ]});
 
   let tab = await openTab(ABOUT_NEWTAB_URL);
   await promiseOnboardingOverlayLoaded(tab.linkedBrowser);
   await BrowserTestUtils.synthesizeMouseAtCenter("#onboarding-overlay-button", {}, tab.linkedBrowser);
   await promiseOnboardingOverlayOpened(tab.linkedBrowser);
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = gBrowser.contentDocumentAsCPOW;
   let doms = doc.querySelectorAll(".onboarding-tour-item");
   is(doms.length, CUSTOM_UPDATE_TOURs.length, "has exact tour numbers");
   doms.forEach((dom, idx) => {
     is(CUSTOM_UPDATE_TOURs[idx], dom.id, "contain defined onboarding id");
   });
 
   await BrowserTestUtils.removeTab(tab);

--- a/browser/modules/test/browser/formValidation/browser_form_validation.js
+++ b/browser/modules/test/browser/formValidation/browser_form_validation.js
@@ -341,17 +341,16 @@ add_task(async function() {
         gObserver.notifyInvalidSubmit = function() {};
         resolve();
       });
     };
 
     Services.obs.addObserver(gObserver, "invalidformsubmit");
 
     executeSoon(function() {
-      // eslint-disable-next-line mozilla/no-cpows-in-tests
       browser.contentDocument.getElementById("s").click();
     });
   });
 
   await notifierPromise;
 
   gBrowser.removeTab(gBrowser.getTabForBrowser(browser));
 });
@@ -387,17 +386,16 @@ add_task(async function() {
 
   let popupShownPromise = BrowserTestUtils.waitForEvent(gInvalidFormPopup, "popupshown");
   await clickChildElement(browser);
   await popupShownPromise;
 
   checkPopupShow();
   await checkChildFocus(browser, gInvalidFormPopup.firstChild.textContent);
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let inputPromise = BrowserTestUtils.waitForEvent(gBrowser.contentDocument.getElementById("i"), "input");
   EventUtils.sendString("f");
   await inputPromise;
 
   // Now, the element suffers from another error, the message should have
   // been updated.
   await new Promise((resolve, reject) => {
     // XXXndeakin This isn't really going to work when the content is another process

--- a/devtools/.eslintrc.js
+++ b/devtools/.eslintrc.js
@@ -13,17 +13,16 @@ module.exports = {
     "require": true,
   },
   "rules": {
     // These are the rules that have been configured so far to match the
     // devtools coding style.
 
     // Rules from the mozilla plugin
     "mozilla/no-aArgs": "error",
-    "mozilla/no-cpows-in-tests": "error",
     "mozilla/no-single-arg-cu-import": "error",
     // See bug 1224289.
     "mozilla/reject-importGlobalProperties": "error",
     // devtools/shared/platform is special; see the README.md in that
     // directory for details.  We reject requires using explicit
     // subdirectories of this directory.
     "mozilla/reject-some-requires": ["error", "^devtools/shared/platform/(chome|content)/"],
     "mozilla/var-only-at-top-level": "error",

--- a/devtools/client/debugger/new/test/mochitest/head.js
+++ b/devtools/client/debugger/new/test/mochitest/head.js
@@ -774,17 +774,17 @@ function waitForActive(dbg) {
  * @static
  */
 function invokeInTab(fnc, ...args) {
   info(`Invoking in tab: ${fnc}(${args.map(uneval).join(",")})`);
   return ContentTask.spawn(gBrowser.selectedBrowser, { fnc, args }, function*({
     fnc,
     args
   }) {
-    content.wrappedJSObject[fnc](...args); // eslint-disable-line mozilla/no-cpows-in-tests, max-len
+    content.wrappedJSObject[fnc](...args);
   });
 }
 
 const isLinux = Services.appinfo.OS === "Linux";
 const isMac = Services.appinfo.OS === "Darwin";
 const cmdOrCtrl = isLinux ? { ctrlKey: true } : { metaKey: true };
 const shiftOrAlt = isMac
   ? { accelKey: true, shiftKey: true }

--- a/devtools/client/netmonitor/test/browser_net_resend_cors.js
+++ b/devtools/client/netmonitor/test/browser_net_resend_cors.js
@@ -88,17 +88,16 @@ add_task(function* () {
       // Wait for both requestPostData & responseContent payloads arrived.
       yield waitUntil(() => {
         item = getRequestById(store.getState(), item.id);
         return item.responseContent && item.requestPostData;
       });
 
       is(item.requestPostData.postData.text, "post-data",
         "The POST request has the right POST data");
-      // eslint-disable-next-line mozilla/no-cpows-in-tests
       is(item.responseContent.content.text, "Access-Control-Allow-Origin: *",
         "The POST response has the right content");
     }
   }
 
   info("Finishing the test");
   return teardown(monitor);
 });

--- a/devtools/client/responsive.html/test/browser/browser_page_state.js
+++ b/devtools/client/responsive.html/test/browser/browser_page_state.js
@@ -41,28 +41,26 @@ add_task(async function () {
 
   // Click on content to set an altered state that would be lost on reload
   await BrowserTestUtils.synthesizeMouseAtCenter("body", {}, browser);
 
   let { ui } = await openRDM(tab);
 
   // Check color inside the viewport
   let color = await spawnViewportTask(ui, {}, function () {
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     return content.getComputedStyle(content.document.body)
                   .getPropertyValue("background-color");
   });
   is(color, "rgb(0, 128, 0)",
      "Content is still modified from click in viewport");
 
   await closeRDM(tab);
 
   // Check color back in the browser tab
   color = await ContentTask.spawn(browser, {}, async function () {
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     return content.getComputedStyle(content.document.body)
                   .getPropertyValue("background-color");
   });
   is(color, "rgb(0, 128, 0)",
      "Content is still modified from click in browser tab");
 
   // Check session history state
   history = await getSessionHistory(browser);

--- a/devtools/client/shared/test/browser_toolbar_webconsole_errors_count.js
+++ b/devtools/client/shared/test/browser_toolbar_webconsole_errors_count.js
@@ -1,13 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
    http://creativecommons.org/publicdomain/zero/1.0/ */
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 "use strict";
 
 // Tests that the developer toolbar errors count works properly.
 
 const {gDevToolsBrowser} = require("devtools/client/framework/devtools-browser");
 
 // Use the old webconsole since this is directly accessing old DOM, and
 // the error count isn't reset when pressing the clear button in new one

--- a/devtools/client/sourceeditor/test/browser_css_autocompletion.js
+++ b/devtools/client/sourceeditor/test/browser_css_autocompletion.js
@@ -75,19 +75,17 @@ let index = 0;
 let completer = null;
 let progress;
 let progressDiv;
 let inspector;
 
 function test() {
   waitForExplicitFinish();
   addTab(TEST_URI).then(function () {
-    /* eslint-disable mozilla/no-cpows-in-tests */
     doc = gBrowser.contentDocumentAsCPOW;
-    /* eslint-enable mozilla/no-cpows-in-tests */
     runTests();
   });
 }
 
 function runTests() {
   progress = doc.getElementById("progress");
   progressDiv = doc.querySelector("#progress > div");
   let target = TargetFactory.forTab(gBrowser.selectedTab);

--- a/devtools/client/sourceeditor/test/browser_css_getInfo.js
+++ b/devtools/client/sourceeditor/test/browser_css_getInfo.js
@@ -123,19 +123,17 @@ const TEST_URI = "data:text/html;charset
    " </html>"
   ].join("\n"));
 
 let doc = null;
 function test() {
   waitForExplicitFinish();
   gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser);
   BrowserTestUtils.browserLoaded(gBrowser.selectedBrowser).then(() => {
-    /* eslint-disable mozilla/no-cpows-in-tests */
     doc = gBrowser.contentDocumentAsCPOW;
-    /* eslint-enable mozilla/no-cpows-in-tests */
     runTests();
   });
   gBrowser.loadURI(TEST_URI);
 }
 
 function runTests() {
   let completer = new CSSCompleter({
     cssProperties: getClientCssProperties()

--- a/devtools/client/sourceeditor/test/browser_css_statemachine.js
+++ b/devtools/client/sourceeditor/test/browser_css_statemachine.js
@@ -54,19 +54,17 @@ const TEST_URI = "data:text/html;charset
    " </html>"
   ].join("\n"));
 
 var doc = null;
 function test() {
   waitForExplicitFinish();
   gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser, TEST_URI);
   BrowserTestUtils.browserLoaded(gBrowser.selectedBrowser).then(() => {
-    /* eslint-disable mozilla/no-cpows-in-tests */
     doc = gBrowser.contentDocumentAsCPOW;
-    /* eslint-enable mozilla/no-cpows-in-tests */
     runTests();
   });
 }
 
 function runTests() {
   let completer = new CSSCompleter({
     cssProperties: getClientCssProperties()
   });

--- a/devtools/server/tests/browser/browser_markers-docloading-01.js
+++ b/devtools/server/tests/browser/browser_markers-docloading-01.js
@@ -6,17 +6,16 @@
  */
 "use strict";
 
 const { TimelineFront } = require("devtools/shared/fronts/timeline");
 const MARKER_NAMES = ["document::DOMContentLoaded", "document::Load"];
 
 add_task(async function () {
   let browser = await addTab(MAIN_DOMAIN + "doc_innerHTML.html");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = browser.contentDocumentAsCPOW;
 
   initDebuggerServer();
   let client = new DebuggerClient(DebuggerServer.connectPipe());
   let form = await connectDebuggerClient(client);
   let front = TimelineFront(client, form);
   let rec = await front.start({ withMarkers: true });
 

--- a/devtools/server/tests/browser/browser_markers-docloading-02.js
+++ b/devtools/server/tests/browser/browser_markers-docloading-02.js
@@ -6,17 +6,16 @@
  */
 "use strict";
 
 const { TimelineFront } = require("devtools/shared/fronts/timeline");
 const MARKER_NAMES = ["document::DOMContentLoaded", "document::Load"];
 
 add_task(async function () {
   let browser = await addTab(MAIN_DOMAIN + "doc_innerHTML.html");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = browser.contentDocumentAsCPOW;
 
   initDebuggerServer();
   let client = new DebuggerClient(DebuggerServer.connectPipe());
   let form = await connectDebuggerClient(client);
   let front = TimelineFront(client, form);
   let rec = await front.start({ withMarkers: true, withDocLoadingEvents: true });
 

--- a/devtools/server/tests/browser/browser_markers-docloading-03.js
+++ b/devtools/server/tests/browser/browser_markers-docloading-03.js
@@ -6,17 +6,16 @@
  */
 "use strict";
 
 const { TimelineFront } = require("devtools/shared/fronts/timeline");
 const MARKER_NAMES = ["document::DOMContentLoaded", "document::Load"];
 
 add_task(async function () {
   let browser = await addTab(MAIN_DOMAIN + "doc_innerHTML.html");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = browser.contentDocumentAsCPOW;
 
   initDebuggerServer();
   let client = new DebuggerClient(DebuggerServer.connectPipe());
   let form = await connectDebuggerClient(client);
   let front = TimelineFront(client, form);
   let rec = await front.start({ withDocLoadingEvents: true });
 

--- a/devtools/server/tests/browser/browser_storage_dynamic_windows.js
+++ b/devtools/server/tests/browser/browser_storage_dynamic_windows.js
@@ -158,20 +158,18 @@ function testAddIframe(front) {
 
     let endTestReloaded = () => {
       front.off("stores-update", onStoresUpdate);
       resolve();
     };
 
     front.on("stores-update", onStoresUpdate);
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let iframe = gBrowser.contentDocumentAsCPOW.createElement("iframe");
     iframe.src = ALT_DOMAIN_SECURED + "storage-secured-iframe.html";
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     gBrowser.contentDocumentAsCPOW.querySelector("body").appendChild(iframe);
   });
 }
 
 function testRemoveIframe(front) {
   info("Testing if iframe removal works properly");
   return new Promise(resolve => {
     let shouldBeEmpty = {

--- a/devtools/server/tests/browser/browser_storage_updates.js
+++ b/devtools/server/tests/browser/browser_storage_updates.js
@@ -293,17 +293,16 @@ function storesCleared(data) {
 async function finishTests(client) {
   await client.close();
   DebuggerServer.destroy();
   finish();
 }
 
 add_task(async function () {
   let browser = await addTab(MAIN_DOMAIN + "storage-updates.html");
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   let doc = browser.contentDocumentAsCPOW;
 
   initDebuggerServer();
 
   let client = new DebuggerClient(DebuggerServer.connectPipe());
   let form = await connectDebuggerClient(client);
   let front = StorageFront(client, form);
   let win = doc.defaultView.wrappedJSObject;

--- a/toolkit/components/narrate/test/browser_narrate.js
+++ b/toolkit/components/narrate/test/browser_narrate.js
@@ -1,16 +1,14 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 "use strict";
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 registerCleanupFunction(teardown);
 
 add_task(async function testNarrate() {
   setup();
 
   await spawnInNewReaderTab(TEST_ARTICLE, async function() {
     let TEST_VOICE = "urn:moz-tts:fake:teresa";
     let $ = content.document.querySelector.bind(content.document);

--- a/toolkit/components/narrate/test/browser_narrate_language.js
+++ b/toolkit/components/narrate/test/browser_narrate_language.js
@@ -1,16 +1,14 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 "use strict";
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 registerCleanupFunction(teardown);
 
 add_task(async function testVoiceselectDropdownAutoclose() {
   setup("automatic", true);
 
   await spawnInNewReaderTab(TEST_ARTICLE, async function() {
     let $ = content.document.querySelector.bind(content.document);
 

--- a/toolkit/components/narrate/test/browser_voiceselect.js
+++ b/toolkit/components/narrate/test/browser_voiceselect.js
@@ -1,16 +1,14 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 "use strict";
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 registerCleanupFunction(teardown);
 
 add_task(async function testVoiceselectDropdownAutoclose() {
   setup();
 
   await spawnInNewReaderTab(TEST_ARTICLE, async function() {
     let $ = content.document.querySelector.bind(content.document);
 

--- a/toolkit/components/narrate/test/browser_word_highlight.js
+++ b/toolkit/components/narrate/test/browser_word_highlight.js
@@ -1,16 +1,14 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 "use strict";
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 registerCleanupFunction(teardown);
 
 add_task(async function testNarrate() {
   setup("urn:moz-tts:fake:teresa");
 
   await spawnInNewReaderTab(TEST_ARTICLE, async function() {
     let $ = content.document.querySelector.bind(content.document);
 

--- a/toolkit/components/normandy/test/browser/browser_about_preferences.js
+++ b/toolkit/components/normandy/test/browser/browser_about_preferences.js
@@ -1,12 +1,10 @@
 "use strict";
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 ChromeUtils.import("resource://gre/modules/Services.jsm", this);
 
 const OPT_OUT_PREF = "app.shield.optoutstudies.enabled";
 const FHR_PREF = "datareporting.healthreport.uploadEnabled";
 
 function withPrivacyPrefs(testFunc) {
   return async (...args) => (
     BrowserTestUtils.withNewTab("about:preferences#privacy", async browser => (

--- a/toolkit/components/normandy/test/browser/browser_about_studies.js
+++ b/toolkit/components/normandy/test/browser/browser_about_studies.js
@@ -10,17 +10,16 @@ return async (...args) => (
       testFunc(...args, browser)
     ))
   );
 }
 
 decorate_task(
   withAboutStudies,
   async function testAboutStudiesWorks(browser) {
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     ok(browser.contentDocumentAsCPOW.getElementById("app"), "App element was found");
   }
 );
 
 decorate_task(
   withPrefEnv({
     set: [["app.normandy.shieldLearnMoreUrl", "http://test/%OS%/"]],
   }),

--- a/toolkit/components/payments/test/browser/browser_host_name.js
+++ b/toolkit/components/payments/test/browser/browser_host_name.js
@@ -5,17 +5,16 @@ async function withBasicRequestDialogFor
     methodData: [PTU.MethodData.basicCard],
     details: PTU.Details.total60USD,
   };
   await spawnInDialogForMerchantTask(PTU.ContentTasks.createRequest, dialogTaskFn, args, {
     origin,
   });
 }
 
-/* eslint-disable mozilla/no-cpows-in-tests */
 add_task(async function test_host() {
   await withBasicRequestDialogForOrigin("https://example.com", () => {
     is(content.document.querySelector("#host-name").textContent, "example.com",
        "Check basic host name");
   });
 });
 
 add_task(async function test_host_subdomain() {

--- a/toolkit/components/payments/test/browser/browser_profile_storage.js
+++ b/toolkit/components/payments/test/browser/browser_profile_storage.js
@@ -1,13 +1,10 @@
 "use strict";
 
-// Disable CPOW checks because they have false-positives from use of ContentTask in a helper.
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 const methodData = [PTU.MethodData.basicCard];
 const details = PTU.Details.total60USD;
 
 add_task(async function test_initial_state() {
   let onChanged = TestUtils.topicObserved("formautofill-storage-changed",
                                           (subject, data) => data == "add");
   let address1GUID = formAutofillStorage.addresses.add({
     "given-name": "Timothy",

--- a/toolkit/components/payments/test/browser/browser_request_serialization.js
+++ b/toolkit/components/payments/test/browser/browser_request_serialization.js
@@ -1,13 +1,10 @@
 "use strict";
 
-// Disable CPOW checks because they have false-positives from use of ContentTask in a helper.
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 add_task(async function test_serializeRequest_displayItems() {
   const testTask = ({methodData, details}) => {
     let contentWin = Cu.waiveXrays(content);
     let store = contentWin.document.querySelector("payment-dialog").requestStore;
     let state = store && store.getState();
     ok(state, "got request store state");
 
     let expected = details;

--- a/toolkit/components/payments/test/browser/browser_request_summary.js
+++ b/toolkit/components/payments/test/browser/browser_request_summary.js
@@ -1,11 +1,10 @@
 "use strict";
 
 add_task(async function test_summary() {
   await BrowserTestUtils.withNewTab({
     gBrowser,
     url: "resource://payments/paymentRequest.xhtml",
   }, async browser => {
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     ok(browser.contentDocumentAsCPOW.getElementById("cancel"), "Cancel button exists");
   });
 });

--- a/toolkit/components/payments/test/browser/browser_total.js
+++ b/toolkit/components/payments/test/browser/browser_total.js
@@ -1,11 +1,10 @@
 "use strict";
 
-/* eslint-disable mozilla/no-cpows-in-tests */
 add_task(async function test_total() {
   const testTask = ({methodData, details}) => {
     is(content.document.querySelector("#total > currency-amount").textContent,
        "$60.00",
        "Check total currency amount");
   };
   const args = {
     methodData: [PTU.MethodData.basicCard],

--- a/toolkit/components/reader/test/browser_readerMode_with_anchor.js
+++ b/toolkit/components/reader/test/browser_readerMode_with_anchor.js
@@ -24,17 +24,16 @@ add_task(async function() {
 });
 
 add_task(async function() {
   await BrowserTestUtils.withNewTab(TEST_PATH + "readerModeArticle.html", async function(browser) {
     let pageShownPromise = BrowserTestUtils.waitForContentEvent(browser, "AboutReaderContentReady");
     let readerButton = document.getElementById("reader-mode-button");
     readerButton.click();
     await pageShownPromise;
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     is(gBrowser.contentDocumentAsCPOW.documentElement.scrollTop, 0, "scrollTop should be 0");
     await BrowserTestUtils.synthesizeMouseAtCenter("#foo-anchor", {}, browser);
     await ContentTask.spawn(browser, null, async function() {
       let foo = content.document.getElementById("foo");
       ok(foo, "foo element should be in document");
       let {scrollTop} = content.document.documentElement;
       let {offsetTop} = foo;
       Assert.lessOrEqual(Math.abs(scrollTop - offsetTop), 1,

--- a/toolkit/content/tests/browser/browser_datetime_datepicker.js
+++ b/toolkit/content/tests/browser/browser_datetime_datepicker.js
@@ -162,17 +162,16 @@ add_task(async function test_datepicker_
   await helper.openPicker(`data:text/html, <input type="date" value="${inputValue}">`);
   // Click the first item (top-left corner) of the calendar
   helper.click(helper.getElement(DAYS_VIEW).children[0]);
   await ContentTask.spawn(helper.tab.linkedBrowser, {}, async function() {
     let inputEl = content.document.querySelector("input");
     await ContentTaskUtils.waitForEvent(inputEl, "input");
   });
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   Assert.equal(gBrowser.contentDocumentAsCPOW.querySelector("input").value, firstDayOnCalendar);
 
   await helper.tearDown();
 });
 
 /**
  * Make sure picker is in correct state when it is reopened.
  */

--- a/toolkit/content/tests/browser/browser_saveImageURL.js
+++ b/toolkit/content/tests/browser/browser_saveImageURL.js
@@ -32,17 +32,16 @@ add_task(async function preferred_API() 
     url: IMAGE_PAGE,
   }, async function(browser) {
     let url = await ContentTask.spawn(browser, null, async function() {
       let image = content.document.getElementById("image");
       return image.href;
     });
 
     saveImageURL(url, "image.jpg", null, true, false, null, null, null, null, false);
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let channel = gBrowser.contentDocumentAsCPOW.docShell.currentDocumentChannel;
     if (channel) {
       ok(true, channel.QueryInterface(Ci.nsIHttpChannelInternal)
                       .channelIsForDownload);
 
       // Throttleable is the only class flag assigned to downloads.
       ok(channel.QueryInterface(Ci.nsIClassOfService).classFlags,
          Ci.nsIClassOfService.Throttleable);
@@ -69,17 +68,16 @@ add_task(async function deprecated_API()
       return image.href;
     });
 
     // Now get the document directly from content. If we run this test with
     // e10s-enabled, this will be a CPOW, which is forbidden. We'll just
     // pass the XUL document instead to test this interface.
     let doc = document;
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     let channel = gBrowser.contentDocumentAsCPOW.docShell.currentDocumentChannel;
     if (channel) {
       ok(true, channel.QueryInterface(Ci.nsIHttpChannelInternal)
                       .channelIsForDownload);
 
       // Throttleable is the only class flag assigned to downloads.
       ok(channel.QueryInterface(Ci.nsIClassOfService).classFlags,
          Ci.nsIClassOfService.Throttleable);

--- a/toolkit/content/tests/browser/browser_save_resend_postdata.js
+++ b/toolkit/content/tests/browser/browser_save_resend_postdata.js
@@ -22,30 +22,28 @@ function test() {
   gBrowser.addEventListener("pageshow", function pageShown(event) {
     if (event.target.location == "about:blank")
       return;
     gBrowser.removeEventListener("pageshow", pageShown);
 
     // Submit the form in the outer page, then wait for both the outer
     // document and the inner frame to be loaded again.
     gBrowser.addEventListener("DOMContentLoaded", handleOuterSubmit);
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     gBrowser.contentDocument.getElementById("postForm").submit();
   });
 
   var framesLoaded = 0;
   var innerFrame;
 
   function handleOuterSubmit() {
     if (++framesLoaded < 2)
       return;
 
     gBrowser.removeEventListener("DOMContentLoaded", handleOuterSubmit);
 
-    // eslint-disable-next-line mozilla/no-cpows-in-tests
     innerFrame = gBrowser.contentDocument.getElementById("innerFrame");
 
     // Submit the form in the inner page.
     gBrowser.addEventListener("DOMContentLoaded", handleInnerSubmit);
     innerFrame.contentDocument.getElementById("postForm").submit();
   }
 
   function handleInnerSubmit() {

--- a/toolkit/mozapps/extensions/test/browser/browser_bug562797.js
+++ b/toolkit/mozapps/extensions/test/browser/browser_bug562797.js
@@ -1,14 +1,13 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 /* eslint max-nested-callbacks: ["warn", 12] */
-/* eslint-disable mozilla/no-cpows-in-tests */
 
 /**
  * Tests that history navigation works for the add-ons manager.
  */
 
 const MAIN_URL = "https://example.com/" + RELATIVE_DIR + "discovery.html";
 const SECOND_URL = "https://example.com/" + RELATIVE_DIR + "releaseNotes.xhtml";
 

--- a/toolkit/mozapps/extensions/test/browser/browser_discovery.js
+++ b/toolkit/mozapps/extensions/test/browser/browser_discovery.js
@@ -169,17 +169,16 @@ function clickLink(aId, aCallback) {
   var browser = gManagerWindow.document.getElementById("discover-browser");
   browser.addProgressListener(gProgressListener);
 
   gLoadCompleteCallback = function() {
     browser.removeProgressListener(gProgressListener);
     aCallback();
   };
 
-  // eslint-disable-next-line mozilla/no-cpows-in-tests
   var link = browser.contentDocument.getElementById(aId);
   EventUtils.sendMouseEvent({type: "click"}, link);
 
   executeSoon(function() {
     ok(isLoading(), "Clicking a link should show the loading pane");
   });
 }
 

--- a/toolkit/mozapps/extensions/test/browser/browser_discovery_install.js
+++ b/toolkit/mozapps/extensions/test/browser/browser_discovery_install.js
@@ -1,14 +1,12 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
-/* eslint-disable mozilla/no-cpows-in-tests */
-
 // Tests that the discovery view can install add-ons correctly
 
 const MAIN_URL = "https://example.com/" + RELATIVE_DIR + "discovery_install.html";
 const GOOD_FRAMED_URL = "https://example.com/" + RELATIVE_DIR + "discovery_frame.html";
 const BAD_FRAMED_URL = "https://example.org/" + RELATIVE_DIR + "discovery_frame.html";
 
 const PREF_INSTALL_REQUIREBUILTINCERTS = "extensions.install.requireBuiltInCerts";
 

--- a/tools/lint/docs/linters/eslint-plugin-mozilla.rst
+++ b/tools/lint/docs/linters/eslint-plugin-mozilla.rst
@@ -165,38 +165,16 @@ first letter is a prefix that indicates 
 
 no-compare-against-boolean-literals
 -----------------------------------
 
 Checks that boolean expressions do not compare against literal values
 of `true` or `false`. This is to prevent overly verbose code such as
 `if (isEnabled == true)` when `if (isEnabled)` would suffice.
 
-no-cpows-in-tests
------------------
-
-This rule checks if the file is a browser mochitest and, if so, checks for
-possible CPOW usage by checking for the following strings:
-
-- ``gBrowser.contentWindow``
-- ``gBrowser.contentDocument``
-- ``gBrowser.selectedBrowser.contentWindow``
-- ``browser.contentDocument``
-- ``window.content``
-- ``content``
-- ``content.``
-
-Note: These are string matches so we will miss situations where the parent
-object is assigned to another variable e.g.:
-
-.. code-block:: js
-
-    var b = gBrowser;
-    b.content // Would not be detected as a CPOW.
-
 no-define-cc-etc
 ----------------
 
 This disallows statements such as:
 
 .. code-block:: js
 
    var Cc = Components.classes;
@@ -335,17 +313,16 @@ Example
 Example configuration:
 
 .. code-block:: js
 
    "rules": {
      "mozilla/balanced-listeners": 2,
      "mozilla/mark-test-function-used": 1,
      "mozilla/var-only-at-top-level": 1,
-     "mozilla/no-cpows-in-tests": 1,
    }
 
 Tests
 =====
 
 The tests for eslint-plugin-mozilla are run via `mochajs`_ on top of node. Most
 of the tests use the `ESLint Rule Unit Test framework`_.
 

--- a/tools/lint/eslint/eslint-plugin-mozilla/lib/configs/browser-test.js
+++ b/tools/lint/eslint/eslint-plugin-mozilla/lib/configs/browser-test.js
@@ -56,12 +56,11 @@ module.exports = {
   "plugins": [
     "mozilla"
   ],
 
   "rules": {
     "mozilla/import-content-task-globals": "error",
     "mozilla/import-headjs-globals": "error",
     "mozilla/mark-test-function-used": "error",
-    "mozilla/no-arbitrary-setTimeout": "error",
-    "mozilla/no-cpows-in-tests": "error"
+    "mozilla/no-arbitrary-setTimeout": "error"
   }
 };

--- a/tools/lint/eslint/eslint-plugin-mozilla/lib/index.js
+++ b/tools/lint/eslint/eslint-plugin-mozilla/lib/index.js
@@ -40,17 +40,16 @@ module.exports = {
       require("../lib/rules/import-content-task-globals"),
     "import-globals": require("../lib/rules/import-globals"),
     "import-headjs-globals": require("../lib/rules/import-headjs-globals"),
     "mark-exported-symbols-as-used": require("../lib/rules/mark-exported-symbols-as-used"),
     "mark-test-function-used": require("../lib/rules/mark-test-function-used"),
     "no-aArgs": require("../lib/rules/no-aArgs"),
     "no-arbitrary-setTimeout": require("../lib/rules/no-arbitrary-setTimeout"),
     "no-compare-against-boolean-literals": require("../lib/rules/no-compare-against-boolean-literals"),
-    "no-cpows-in-tests": require("../lib/rules/no-cpows-in-tests"),
     "no-define-cc-etc": require("../lib/rules/no-define-cc-etc"),
     "no-single-arg-cu-import": require("../lib/rules/no-single-arg-cu-import"),
     "no-import-into-var-and-global":
       require("../lib/rules/no-import-into-var-and-global.js"),
     "no-task": require("../lib/rules/no-task"),
     "no-useless-parameters": require("../lib/rules/no-useless-parameters"),
     "no-useless-removeEventListener":
       require("../lib/rules/no-useless-removeEventListener"),

deleted file mode 100644
--- a/tools/lint/eslint/eslint-plugin-mozilla/lib/rules/no-cpows-in-tests.js
+++ /dev/null
@@ -1,181 +0,0 @@
-/**
- * @fileoverview Prevent access to CPOWs in browser mochitests.
- *
- * This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/.
- */
-
-"use strict";
-
-// -----------------------------------------------------------------------------
-// Rule Definition
-// -----------------------------------------------------------------------------
-
-var helpers = require("../helpers");
-
-var cpows = [
-  /^gBrowser\.contentWindow/,
-  /^gBrowser\.contentDocument/,
-  /^gBrowser\.selectedBrowser\.contentWindow/,
-  /^browser\.contentDocument/,
-  /^window\.content/
-];
-
-// Keep track of where the last error is reported so to avoid reporting the same
-// expression (e.g., window.content.X vs window.content). Resets for each file.
-var lastErrorStart;
-
-// Keep track of whether we've entered a ContentTask.spawn call where accesses
-// to "content" are *not* CPOW. Resets when exiting the call.
-var isInContentTask = false;
-
-module.exports = function(context) {
-  // ---------------------------------------------------------------------------
-  // Helpers
-  // ---------------------------------------------------------------------------
-
-  function showError(node, identifier) {
-    if (isInContentTask) {
-      return;
-    }
-
-    // Avoid showing partial expressions errors when one already errored.
-    if (node.start === lastErrorStart) {
-      return;
-    }
-    lastErrorStart = node.start;
-
-    context.report({
-      node,
-      message: identifier +
-               " is a possible Cross Process Object Wrapper (CPOW)."
-    });
-  }
-
-  function hasLocalContentVariable(node) {
-    // Walk up the parents, see if we can find if "content" is a local variable.
-    let parent = node;
-    do {
-      parent = parent.parent;
-
-      // Don't error if 'content' is one of the function parameters.
-      if (helpers.getIsFunctionNode(parent) &&
-          context.getDeclaredVariables(parent).some(variable => variable.name === "content")) {
-        return true;
-      } else if (parent.type === "BlockStatement" || parent.type === "Program") {
-        // Don't error if the block or program includes their own definition of content.
-        for (let item of parent.body) {
-          if (item.type === "VariableDeclaration" && item.declarations.length) {
-            for (let declaration of item.declarations) {
-              if (declaration.id && declaration.id.name === "content") {
-                return true;
-              }
-            }
-          }
-        }
-      }
-    } while (parent.parent);
-    return false;
-  }
-
-  function isContentTask(node) {
-    return node &&
-           node.type === "MemberExpression" &&
-           node.property.type === "Identifier" &&
-           node.property.name === "spawn" &&
-           node.object.type === "Identifier" &&
-           node.object.name === "ContentTask";
-  }
-
-  // ---------------------------------------------------------------------------
-  // Public
-  // ---------------------------------------------------------------------------
-
-  return {
-    CallExpression(node) {
-      if (isContentTask(node.callee)) {
-        isInContentTask = true;
-      }
-    },
-
-    "CallExpression:exit": function(node) {
-      if (isContentTask(node.callee)) {
-        isInContentTask = false;
-      }
-    },
-
-    Program() {
-      lastErrorStart = undefined;
-    },
-
-    MemberExpression(node) {
-      if (helpers.getTestType(context) != "browser") {
-        return;
-      }
-
-      var expression = context.getSource(node);
-
-      // Only report a single CPOW error per node -- so if checking
-      // |cpows| reports one, don't report another below.
-      var someCpowFound = cpows.some(function(cpow) {
-        if (cpow.test(expression)) {
-          showError(node, expression);
-          return true;
-        }
-        return false;
-      });
-
-      // Specially scope checks for "context." to avoid false positives.
-      if (!someCpowFound && /^content\./.test(expression)) {
-        // Don't error if we're multiple scopes deep. For now we only care about
-        // 2 scopes: global (length = 0) or immediately called by add_task.
-        // Ideally, we would care about any scope, but figuring out whether
-        // "context" is CPOW-or-not depends on how functions are defined and
-        // called -- both aspects are especially complex with head.js helpers.
-        // https://bugzilla.mozilla.org/show_bug.cgi?id=1417017#c9
-        const scopes = context.getAncestors().filter(helpers.getIsFunctionNode);
-        if (scopes.length > 1 || scopes.length === 1 &&
-            (!scopes[0].parent.callee || scopes[0].parent.callee.name !== "add_task")) {
-          return;
-        }
-
-        // Don't error if there's a locally scoped "content"
-        if (hasLocalContentVariable(node)) {
-          return;
-        }
-
-        showError(node, expression);
-      }
-    },
-
-    Identifier(node) {
-      if (helpers.getTestType(context) != "browser") {
-        return;
-      }
-
-      if (node.name !== "content" ||
-          // Don't complain if this is part of a member expression - the
-          // MemberExpression() function will handle those.
-          node.parent.type === "MemberExpression" ||
-          // If this is a declared variable in a function, then don't complain.
-          node.parent.type === "FunctionDeclaration") {
-        return;
-      }
-
-      // Don't error in the case of `let content = foo`.
-      if (node.parent.type === "VariableDeclarator" &&
-          node.parent.id && node.parent.id.name === "content") {
-        return;
-      }
-
-      // Don't error if there's a locally scoped "content"
-      if (hasLocalContentVariable(node)) {
-        return;
-      }
-
-      var expression = context.getSource(node);
-      showError(node, expression);
-    }
-  };
-};