--- mozilla-beta/browser/app/profile/firefox.js.defaultbrowser	2013-09-19 22:30:30.000000000 +0800
+++ mozilla-beta/browser/app/profile/firefox.js	2013-09-19 22:31:51.033717317 +0800
@@ -230,7 +230,7 @@ pref("general.autoScroll", true);
 #endif
 
 // At startup, check if we're the default browser and prompt user if not.
-pref("browser.shell.checkDefaultBrowser", true);
+pref("browser.shell.checkDefaultBrowser", false);
 pref("browser.shell.shortcutFavicons",true);
 pref("browser.shell.mostRecentDateSetAsDefault", "");
 pref("browser.shell.skipDefaultBrowserCheck", true);