Ridiculous that this is still going on after so long and so many threads about it. For me, it's only happening on my desktop, using MS Edge.
If I'm on my iPad, I'm signed out.
In fact, I've gotten so used to being permanently signed in on my desktop, that it will be a real shock, should I ever find myself logged out on here!
(BTW: I've tried all the suggestions for clearing history, etc.. Log out on here and it says "signed out". Then I come back in and - hey, presto - I'm still logged on.)
"" A little learning is a dangerous thing."-Alexander Pope