(This has happened on multiple browsers/devices)

I used to be able to sign in, and stay signed in more or less indefinitely on my computers, phones, etc.  I keep getting bouts, including this morning where I'm suddenly signed out on all of my devices. Its even happened in the middle of posts I was writing, including this week.

The concern I have is that means somewhere in the backend its detecting that someone's trying to log in as me with random passwords, or similar, and booting all of my sessions?

Definitely not manually signing out on any of the devices when this happens.  

I'll change my PW, but it is definitely strange.  For what it's worth the cybersecurity posture on the devices is pretty aggressive (Artic Wolf and Crowdstrike).  This generally has happened with Brave browser, but also google chrome.

I have been having the same issues with multiple sites, including arf. I never log off. Arf just logged me out on my phone and I can't get back in. I'll "happily" try changing PW. (Another new PW to remember....aaarrrgh)