XenForo seems to have some of these issues. This happened to me quite a bit over the weekend but it seems to have stopped so far today (crossing fingers). The https could be part of it and it seems intermittent, which is also kind of odd.
Yeah, for the record, watch out for that sneaky little 's'. It seems to have been the cause of my problems.
Firefox has a little ! icon next to the html line to the far left when you connect to the https address and it's a warning of sorts saying the website isn't encrypting information. Going to the non https has solved all of my issues recently
consistent and reproducible for me. using ffox and https://forums.cardhunter.com/forums Go to Card Hunter General Chat sub-forum, I click on any thread then click on the Card Hunter General Chat tab at the top of the page. I'm automatically logged out. Hope it helps.
It seems like this is a common problem with XenForo. One of the weird hiccups I suppose? I've since changed the "user log-out" to an hour (it was set to 15 minutes!) so we'll see if that helps some. In the meantime, please use HTTP instead of HTTPS. Bleh. Thanks for pointing out the issue and everyone's help in diagnosing!
I may have the solution. The "New reply to watched thread" email the link is https: Whenever I click on a https forum link from that email, it logs me out
I changed a setting for us so the default forum URL is http://forums.cardhunter.com rather than https://forums.cardhunter.com. Hopefully that helps work around the problem. I'm not happy with having to turn off secure forum browsing, but it sure does seem to be broken.