Do you get the crash reporter and have submitted a crash report? If you have submitted crash reports, please post the IDs of one or more recent crash reports that start with "bp-". *bp-xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx You can find the report ID of recent crash reports on the "Help -> More Troubleshooting Information" (about:support) page. *click the "All crash Reports" button on this page to open the <b>about:crashes</b> page and see all crash reports. Alternately, you can open about:crashes via the location/address bar. See "Viewing reports outside of Firefox": *https://support.mozilla.org/en-US/kb/mozillacrashreporter <hr> *https://support.mozilla.org/en-US/kb/troubleshoot-firefox-crashes-closing-or-quitting *https://support.mozilla.org/en-US/kb/firefox-crashes-asking-support ----- Try to start Firefox in <b>Troubleshoot Mode</b> to see if that works and possibly create a new profile. *Windows: hold down the Shift key while starting Firefox *Mac: hold down the Options key while starting Firefox *https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode You can create a new profile as a quick test to see if your current profile is causing the problem. See "Creating a profile": *https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles If the new profile works, you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems. *https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile ----- Boot the computer in Windows Safe Mode with network support to see if that has effect. *[https://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/] *[https://www.digitalcitizen.life/4-ways-boot-safe-mode-windows-10/]