--- a/devtools/client/webconsole/new-console-output/test/mochitest/browser.ini
+++ b/devtools/client/webconsole/new-console-output/test/mochitest/browser.ini
@@ -12,19 +12,16 @@ support-files =
   source-mapped.scss
   test_bug_1010953_cspro.html
   test_bug_1010953_cspro.html^headers^
   test_bug_1247459_violation.html
   test_bug_770099_violation.html
   test_bug_770099_violation.html^headers^
   test_console_csp_ignore_reflected_xss_message.html
   test_console_csp_ignore_reflected_xss_message.html^headers^
-  test_bug1092055_shouldwarn.html
-  test_bug1092055_shouldwarn.js
-  test_bug1092055_shouldwarn.js^headers^
   test_hpkp-invalid-headers.sjs
   test_hsts-invalid-headers.sjs
   test-autocomplete-in-stackframe.html
   test-batching.html
   test-bug_1050691_click_function_to_source.html
   test-bug_1050691_click_function_to_source.js
   test-bug_923281_console_log_filter.html
   test-bug_923281_test1.js
@@ -153,16 +150,19 @@ support-files =
   test-reopen-closed-tab.html
   test-repeated-messages.html
   test-result-format-as-string.html
   test-sourcemap-error-01.html
   test-sourcemap-error-01.js
   test-sourcemap-error-02.html
   test-sourcemap-error-02.js
   test-stacktrace-location-debugger-link.html
+  test-subresource-security-error.html
+  test-subresource-security-error.js
+  test-subresource-security-error.js^headers^
   test-trackingprotection-securityerrors.html
   test-webconsole-error-observer.html
   testscript.js
   !/devtools/client/netmonitor/test/sjs_cors-test-server.sjs
   !/image/test/mochitest/blue.png
   !/devtools/client/framework/test/shared-head.js
   !/devtools/client/netmonitor/test/shared-head.js
 [browser_console.js]
@@ -393,18 +393,16 @@ skip-if = true #	Bug 1403450
 skip-if = true #	Bug 1401942
 [browser_webconsole_script_errordoc_urls.js]
 skip-if = true #	Bug 1403454
 # old console skip-if = e10s # Bug 1042253 - webconsole tests disabled with e10s
 [browser_webconsole_scroll.js]
 [browser_webconsole_select_all.js]
 skip-if = true #	Bug 1404359
 [browser_webconsole_show_subresource_security_errors.js]
-skip-if = true # Bug 1408948
-# old console skip-if = e10s && (os == 'win' || os == 'mac') # Bug 1243987
 [browser_webconsole_shows_reqs_in_netmonitor.js]
 [browser_webconsole_sourcemap_css.js]
 [browser_webconsole_sourcemap_error.js]
 [browser_webconsole_sourcemap_invalid.js]
 [browser_webconsole_sourcemap_nosource.js]
 [browser_webconsole_split.js]
 skip-if = true # Bug 1408949
 [browser_webconsole_split_escape_key.js]

--- a/devtools/client/webconsole/new-console-output/test/mochitest/browser_webconsole_show_subresource_security_errors.js
+++ b/devtools/client/webconsole/new-console-output/test/mochitest/browser_webconsole_show_subresource_security_errors.js
@@ -5,29 +5,20 @@
 
 // Ensure non-toplevel security errors are displayed
 
 "use strict";
 
 const TEST_URI = "data:text/html;charset=utf-8,Web Console subresource STS " +
                  "warning test";
 const TEST_DOC = "https://example.com/browser/devtools/client/webconsole/" +
-                 "test/test_bug1092055_shouldwarn.html";
+                 "new-console-output/test/mochitest/test-subresource-security-error.html";
 const SAMPLE_MSG = "specified a header that could not be parsed successfully.";
 
-add_task(function* () {
-  let { browser } = yield loadTab(TEST_URI);
-
-  let hud = yield openConsole();
-
+add_task(async function () {
+  const hud = await openNewTabAndConsole(TEST_URI);
   hud.jsterm.clearOutput();
+  await loadDocument(TEST_DOC);
 
-  let loaded = loadBrowser(browser);
-  BrowserTestUtils.loadURI(browser, TEST_DOC);
-  yield loaded;
+  await waitFor(() => findMessage(hud, SAMPLE_MSG, ".message.warn"));
 
-  yield waitForSuccess({
-    name: "Subresource STS warning displayed successfully",
-    validator: function () {
-      return hud.outputNode.textContent.indexOf(SAMPLE_MSG) > -1;
-    }
-  });
+  ok(true, "non-toplevel security warning message was displayed");
 });

rename from devtools/client/webconsole/new-console-output/test/mochitest/test_bug1092055_shouldwarn.html
rename to devtools/client/webconsole/new-console-output/test/mochitest/test-subresource-security-error.html
--- a/devtools/client/webconsole/new-console-output/test/mochitest/test_bug1092055_shouldwarn.html
+++ b/devtools/client/webconsole/new-console-output/test/mochitest/test-subresource-security-error.html
@@ -1,14 +1,14 @@
 <!DOCTYPE HTML>
 <html>
 <head>
   <meta charset="UTF-8">
   <title>Bug 1092055 - Log console messages for non-top-level security errors</title>
-  <script src="test_bug1092055_shouldwarn.js"></script>
+  <script src="test-subresource-security-error.js"></script>
   <!--
     Any copyright is dedicated to the Public Domain.
     http://creativecommons.org/publicdomain/zero/1.0/
   -->
 </head>
 <body>
 Bug 1092055 - Log console messages for non-top-level security errors
 </body>

rename from devtools/client/webconsole/new-console-output/test/mochitest/test_bug1092055_shouldwarn.js
rename to devtools/client/webconsole/new-console-output/test/mochitest/test-subresource-security-error.js

rename from devtools/client/webconsole/new-console-output/test/mochitest/test_bug1092055_shouldwarn.js^headers^
rename to devtools/client/webconsole/new-console-output/test/mochitest/test-subresource-security-error.js^headers^