Bug 1604751 - disable browser_browser_toolbox_fission_contentframe_inspector.js on Linux_64_QR_debug for frequent failures. r=intermittent-reviewers,bhearsum DONTBUILD

Differential Revision: https://phabricator.services.mozilla.com/D122957

devtools/client/framework/browser-toolbox/test/browser.ini

@@ -28,6 +28,8 @@ prefs =
 [browser_browser_toolbox_debugger.js]
 [browser_browser_toolbox_evaluation_context.js]
 [browser_browser_toolbox_fission_contentframe_inspector.js]
+skip-if =
+  os == 'linux' && bits == 64 && webrender && debug # Bug 1604751
 [browser_browser_toolbox_fission_inspector_webextension.js]
 [browser_browser_toolbox_fission_inspector.js]
 [browser_browser_toolbox_print_preview.js]