If the browser thinks there is a problem, sometimes it will do a refresh.

Refreshing Firefox {web link} is a LAST RESORT ! !

Refreshing Firefox -- easily fix most problems

If you're having problems with Firefox, refreshing it can help. The refresh feature fixes many issues by restoring Firefox to its factory default state while saving your essential information like bookmarks and open tabs. Everything else, like user settings and add-ons, are removed. Note: Refresh saves your old profile to the desktop in a folder called Old Firefox.

Look on your desktop. Do you see a folder called; Old Firefox? Look inside. Look for the folder with the latest creation date.

https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update

Firefox caused a refresh and now I have lost all my extensions etc. A. Why did it do this refresh? B. Is it time for me to now change to a better browser, as now I will have to find all re install all my extensions etc.

Regarding A, usually Firefox will suggest a tune-up if certain performance metrics have fallen below a defined level. Does that sound familiar, or did it happen without asking approval?

Regarding B, if you have set up Firefox Sync, often the extensions will reinstall automatically when you sign in to your account. Maybe it's too late for this round.

This thread has a procedure for fully resurrecting the profile folder inside Old Firefox Data:

https://support.mozilla.org/en-US/questions/1322197#answer-1384732