logging in and out randomly?

When does it happen? On its own when you're not actively using the sites… or just between pageloads, using that site, going from one page to another, you're signed out out of nowhere?

Or "without doing anything" means you come back to work next day, maybe even starting the browser after it's been shut down, and some sites require a login?

(BTW have you confirmed the actual deletion of cookies reported, i.e. inspecting the list of cookies and storage for the site while it works, and observing the same entries disappear once you're signed out?)

I get to work,(home health care aide and work overnight). Client sleeps, when I leave the computer for let's say 15 minutes to do some work tasks, and come back I have to log in again. It will happen 3-4 times a night for a 9 hour shift and it logs me out of yahoo, Instagram , almost everything SAVED site on my computer. I have not deleted any cookies on my own, and it shows they are still there.

If you're using a network you potentially don't manage, do you use a VPN to connect outside? (Can be both a culprit so worth disabling, as well as a thing to try to enable/use in case the client's IP address changes or their provider does something you appear as different connections over time from the outside).

If the cookies and session data is kept intact, and just the services randomly distrust the logged in session, it could be unrelated to cookies but might be impacted by networking or even some security software interfering with the connection (i.e. try disabling any antivirus or malware protection for a bit to see any difference, disabling any addons esp. anything about "privacy" or "tracking", or perhaps even restarting into safe mode from the support tab to Use Troubleshoot Mode in Firefox and try browsing using that for a bit — in case it's something messing with how you appear to the service on the other side).

--At home my computer and my network---so managed of lack of by me! (lol) --At work been there for 5 years no issues until like the past maybe week.--also did not notice any changes---my client would not know how to(Autistic and other issues) so no changes there-- --Don't use a vpn for my emails or for my laptop --same security software I have been using for years, but all of this started like a week ago

--will just keep chalking it up to my stupid luck--but THANK you for the advice and information--will work on it if it keeps bugging me!!

If it happened between restarts or between major updates, it would be understandable. Having the session invalidated just by sitting idle and refreshing later is just wrong.

The troubleshooter mode walkthrough in the previous link tries to eliminate any factors that might interfere with browsing some of the bigger services (esp. from addons) — try running in that mode next time for a while to see any change.