Hi Matthew, it's hard to know the best approach without more information about the problems. Have you already tried a new profile to see whether that allows Firefox to run normally? Here's how: '''New Profile Test''' This takes about 3 minutes, plus the time to test your problem site(s). Inside Firefox, type or paste '''about:profiles''' in the address bar and press Enter/Return to load it. Click the "Create a New Profile" button, then click Next. Assign a name like Aug2020, ignore the option to relocate the profile folder, and click the Finish button. After creating the profile, scroll down to it and click the '''Launch profile in new browser''' button. Firefox should open a new window that looks like a brand new, uncustomized installation. (Your existing Firefox window(s) should not be affected.) Please ignore any tabs enticing you to connect to a Sync account or to activate extensions found on your system so we can get a clean test. ''Do the problem site(s) work any better in the new profile?'' When you are done with the experiment, you can close the extra window without affecting your regular Firefox profile. (Aug2020 will remain available for future testing.) IMPORTANT: Creating a new profile may change your default. If your regular profile has a '''Set as Default Profile''' button after this test, click that to make sure your next startup doesn't yield a surprise.

Also, in general: [[Uninstall Firefox from your computer]]