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Not sure if this is an isolated issue or not but when I log in and tick remember me, after awhile within say 30 mins or so I need to log back in again.
This has happened on my laptop and desktop computer.
This is a funny one as it appears some people experience this issue and some people don't. I can't seem to replicate it myself, which makes it hard to fix.
I assume your browser or something else isn't blocking or removing the cookies somehow?