I'm having lots of trouble with Firefox stability, and even after fresh re-install yesterday, I still have the problem. 1) Sometimes when I start it, it does not start as an App. running on Task Mgr.; it shows as 2 or 3 background F.F. running in Task Mgr. Also, I am unable to get the Task Mgr. to close these down, though sometimes they will close after several minutes. However, then I cannot restart F.F. without the same thing happening. 2) Sometimes, after this happens, A Restart of the pc will allow F.F. to start and run normally, but then the Task Mgr. shows up to 7 F.F. running as active App., and sometimes some others are shown in Background apps. 3) Yesterday (1-29-21), I saved my Profile with all settings, bookmarks, addons, preferences, etc. I then did a complete uninstall of F.F., and downloaded and installed the latest version as of now. I then switched the profile to my saved profile, and it then seemed to start and work normally. However, today I restarted the pc, and had the same identical problems again. 4) Thunderbird seems to work normally. 5) I had the pc checked by the shop at the local Micro Center last week, and they could find nothing wrong in the pc or Windows 10. I've been using Firefox for a long time and really like it, but if I can't get this fixed, I dred having to switch to EDGE and losing all my F.F. addons. Can anybody suggest what is wrong, or if my profile is corrupted somehow?