Hi tunnsee, Does a clean reinstall without the addons do the trick? Another note this bug: [https://bugzilla.mozilla.org/show_bug.cgi?id=947801 Bug 947801 - DNS resolution sporadically fails in Android 4.4 when connected to a VPN ] has a very strange work around that seems that the root cause if a false DNS request? You can check this by enabling Remote debugging in the browser and connecting it to a usb and running adb logcat to capture logs. or check out the developer tools [https://developer.mozilla.org/en-US/docs/Tools/Remote_Debugging/Firefox_for_Android] and make sure Network is enabled. Does putting it into Airplane mode temporarily really act as a work around?