My firefox can't be updated because of Potential Security Issue. I tried to directly download from firefox, but still can't download the new version. I tried to use other browsers to download from this website... still not successfully. https://www.mozilla.org/en-US/firefox/new/?reason=manual-update Here is the detail I got from Edge: " This server couldn't prove that it's download.mozilla.org; its security certificate is from 1099cloud.com. This may be caused by a misconfiguration or an attacker intercepting your connection. " What is '1099cloud.com ', which stops me from downloading anything from firefox website? How can I fix it?