I had to login to Wikipedia on my computer today (I had enabled Dark Mode, I was seeing Light Mode, an alarm that I had been logged out). Then I see I received an email about seeing a new login from an unknown device. Four problems with this: The checkbox says it'll keep me logged in for a year. My last login was when I spotted that Dark Mode was now available, I logged in only a few months ago to set and save Dark Mode. Secondly, this is NOT a new/unknown device! In addition to what I just said about logging in a few months ago, this is my DESKTOP COMPUTER, the only browser I use on it (up-to-date Firefox), and has been my main computer since I built it maybe 6 or so years ago. Thirdly, when clicking the help link in the email (I had hoped I'd find a path to this reporting these errors), it says this is done via cookies via this LoginNotify, which last 180 days, that would be half a year (about), not the promised year. And note I did not delete my cookies (for reasons like this I don't delete cookies unless something is going wrong, then I delete only cookies related to the problem website), nor do I ever use Private browsing, including now. Fourthly, this is my desktop computer of many years, I don't ever want or need to be logged out, we should be able to have non-expiring logins.
I can only conclude that Wikipedia has trouble with multiple devices, which shouldn't happen if this is all via cookies. In addition to this desktop I use/login on an iPad (which is what I'm using to file this bug report), as well as 3 or 4 laptops during this same 6-or-so years (maybe one currently). I find it horribly offensive for the email to call this an "unknown" device when it's well known, and the actual event is an early auto-logout on YOUR side. The email should accurately reflect what actually happened, instead of a lame "(probably you)". A person who is less tech savvy as I am would think there was some issue, if a known device is being called Unknown.