Firefox does not store open tabs or other history to disk in private browsing mode. You could save your list of tabs this way:

(1) Press Ctrl+Shift+D to call up the "Bookmark All Tabs" dialog

(2) Create a name for your folder (like 2025-04-15) and save it

(Repeat in each open window with tabs you want to save)

Then when you start Firefox again, you can go to the Other Bookmarks folder (or wherever that set of tabs was saved) and:

right-click > Open All bookmarks

Then after the tabs open, you can delete the folder since you won't need it again.

I don't want to open tabs from bookmarks every time. It was about using an account. If not in private mode, then maybe it is possible in normal mode?

Restoring your previous session automatically is possible in regular mode, but not in private mode.

I already understood that. I ask: is it possible to make it so that in regular mode, when you log into your account, all tabs are automatically restored along with cookies, and when you log out, all this disappears?

With your Mozilla Account? No, the Sync feature does not upload open private tabs to the Sync cloud.

Also, even for regular windows, open tab Sync doesn't include tab state data like cookies, form data, etc., just title, URL, and last access time. Tab state is only stored in local session history files.