My cookies are being deleted without my permission

What settings do you have for Cookies and Closing Fx?

It is not on "Clear cookies and site data every time you close Firefox". That was the first thing I checked.

How do you tell? Is the manage data list empty after restart?

Is only site data missing, or browsing history too?

Check also "Remember history" vs. "customize history" options, or the "never remember history" options.

jbr, It was my cookies, not my history. When I went on certain sites I had to sign in. I often clear cookie that are unnecessary and when I did that, all my cookies were gone. This is the second time this has happened. I did check my "Remember History" in settings and that's what it's set on. I'm hoping it's not a glitch within Mozilla or Firefox. It could be a husband glitch, he uses my computer often. But when I check, the box isn't checked for "Clear Cookies".

Well you can be signed out by a site just based on… you know… your internet provider rotating addresses, and the like.

To confirm your cookies are gone after a restart, please check the site data list at that point — all of the cookies might still be there, just the site operators no longer associate them with your account. (If the cookie list is empty/short, that's something to look into, yes.)

If you want to perform a test, there's a storage demo e.g. here: mdn.github.io/learning-area/javascript/apis/client-side-storage/indexeddb/notes/ — just put some "testy" "test" in the form and save it. When you return to the site, the same data should be shown there for you. And should persist even after restart. That's the easiest way to see the storages are persisted… or not.