User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:25.7) Gecko/20151012 Firefox/31.9 PaleMoon/25.7.3 Build ID: 20151012160144 Steps to reproduce: For security reasons, I don't like to give myself write access to a folder with commonly accessed executables. So in my Linux profiles, root is the only user that can write to the Firefox program folder. But this means the built-in update mechanism doesn't work. The solution would be to sudo the installer. Now it briefly has write access. Once the update is complete, it goes away. The only catch is that you might need to check to see if you actually need to use gksudo or an equivalent instead of sudo itself. Actual results: Firefox can't upgrade itself on Linux because of security issues. Expected results: Firefox should detect the rights issue and sudo the installer.