--- a/browser/components/preferences/in-content/tests/browser.ini
+++ b/browser/components/preferences/in-content/tests/browser.ini
@@ -13,17 +13,16 @@ support-files =
 [browser_bug1018066_resetScrollPosition.js]
 [browser_bug1020245_openPreferences_to_paneContent.js]
 [browser_change_app_handler.js]
 skip-if = os != "win" # This test tests the windows-specific app selection dialog, so can't run on non-Windows
 [browser_chunk_permissions.js]
 [browser_connection.js]
 [browser_connection_bug388287.js]
 [browser_cookies_exceptions.js]
-skip-if = os == "linux" # See bug 1209521 for re-enabling on Linux
 [browser_healthreport.js]
 skip-if = !healthreport || (os == 'linux' && debug)
 [browser_permissions.js]
 [browser_proxy_backup.js]
 [browser_privacypane_1.js]
 [browser_privacypane_3.js]
 [browser_privacypane_4.js]
 [browser_privacypane_5.js]

--- a/browser/components/preferences/in-content/tests/browser_cookies_exceptions.js
+++ b/browser/components/preferences/in-content/tests/browser_cookies_exceptions.js
@@ -1,13 +1,14 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
 
 function test() {
   waitForExplicitFinish();
+  requestLongerTimeout(2);
   testRunner.runTests();
 }
 
 var testRunner = {
 
   tests:
     [
       {