--- a/testing/profiles/prefs_general.js
+++ b/testing/profiles/prefs_general.js
@@ -39,16 +39,17 @@ user_pref("dom.min_background_timeout_va
 user_pref("test.mousescroll", true);
 user_pref("security.default_personal_cert", "Select Automatically"); // Need to client auth test be w/o any dialogs
 user_pref("network.http.prompt-temp-redirect", false);
 user_pref("media.preload.default", 2); // default = metadata
 user_pref("media.preload.auto", 3); // auto = enough
 user_pref("media.cache_size", 1000);
 user_pref("media.volume_scale", "0.01");
 user_pref("media.test.dumpDebugInfo", true);
+user_pref("media.dormant-on-pause-timeout-ms", -1); // Disable dormant for it breaks some tests.
 user_pref("security.warn_viewing_mixed", false);
 user_pref("app.update.enabled", false);
 user_pref("app.update.staging.enabled", false);
 user_pref("app.update.url.android", "");
 // Make sure GMPInstallManager won't hit the network.
 user_pref("media.gmp-manager.url.override", "http://%(server)s/dummy-gmp-manager.xml");
 user_pref("media.gmp-manager.updateEnabled", false);
 user_pref("dom.w3c_touch_events.enabled", 1);