Hi willson-mark, To see if your current profile is the problem, I suggest you can try to create a new profile. See "Creating a profile": https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues If the new profile works, you can copy files from your previous profile to the new profile; however, be careful not to copy corrupted files to avoid difficulties. http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox Link below is an additional ways for you to fix the error: https://kinsta.com/blog/err_connection_timed_out/ Hope it helps you!