If you believe your firefox version has been hacked, please try these steps: First of all, unninstall firefox since it is clearly infected with something, make sure you did not download it from a random site out there. If you are on iPhone: Download the real firefox on the app store. If you are on any mobile device with android/any linux distro: Go to their respective store and download firefox from there. Please reply if you are still facing issues, zaza :)