--- a/devtools/client/commandline/test/browser_cmd_csscoverage_startstop.js
+++ b/devtools/client/commandline/test/browser_cmd_csscoverage_startstop.js
@@ -32,27 +32,28 @@ add_task(function* () {
 /**
  * Visit all the pages in the test
  */
 function* navigate(usage, options) {
   yield usage.start(options.chromeWindow, options.target);
 
   ok(usage.isRunning(), "csscoverage is running");
 
-  let load1Promise = helpers.listenOnce(options.browser, "load", true);
+  let load1Promise = waitForTabLoad(options.browser);
 
   yield helpers.navigate(PAGE_1, options);
 
   // Wait for the test pages to auto-cycle
   yield load1Promise;
-  is(options.window.location.href, PAGE_1, "page 1 loaded");
+  is(options.browser.currentURI.spec, PAGE_1, "page 1 loaded");
 
   // Page 2 is a frame in page 1. JS in the page navigates to page 3.
-  yield helpers.listenOnce(options.browser, "load", true);
-  is(options.window.location.href, PAGE_3, "page 3 loaded");
+
+  yield waitForTabLoad(options.browser);
+  is(options.browser.currentURI.spec, PAGE_3, "page 3 loaded");
 
   let toolboxReady = gDevTools.once("toolbox-ready");
 
   yield usage.stop();
 
   ok(!usage.isRunning(), "csscoverage not is running");
 
   yield toolboxReady;

--- a/devtools/client/commandline/test/head.js
+++ b/devtools/client/commandline/test/head.js
@@ -23,16 +23,31 @@ function whenDelayedStartupFinished(aWin
   Services.obs.addObserver(function observer(aSubject, aTopic) {
     if (aWindow == aSubject) {
       Services.obs.removeObserver(observer, aTopic);
       executeSoon(aCallback);
     }
   }, "browser-delayed-startup-finished", false);
 }
 
+var waitForTabLoad = function (browser) {
+  return ContentTask.spawn(browser, null, function* () {
+    yield new Promise(done => {
+      let listener = function (event) {
+        // Only consider top document load to ignore iframes
+        if (event.target == content.document) {
+          removeEventListener("load", listener, true);
+          done();
+        }
+      };
+      addEventListener("load", listener, true);
+    });
+  });
+}
+
 /**
  * Force GC on shutdown, because it seems that GCLI can outrun the garbage
  * collector in some situations, which causes test failures in later tests
  * Bug 774619 is an example.
  */
 registerCleanupFunction(function tearDown() {
   window.QueryInterface(Ci.nsIInterfaceRequestor)
       .getInterface(Ci.nsIDOMWindowUtils)