Is this still an issue? The logout link was changed to a hashcode so that people couldn't maliciously trick others into clicking a static logout link. Since the "Remember me" cookies only last a week, this may have resolved itself by now.
Getting the same issue too, guess I didn't test it properly.
As Gemini mentioned, it's only when you have remember me unticked. I can see the logout= link gets passed a string instead of logout/false (possibly changed to patch a bug?), so the issue is probably there.
I'm using an old 3ds XL, Bunny uses a Samsung Mobile, and I'm not quite sure what U.killer uses.
I also would have to drive across a whole city to get to either of their houses, so I'm pretty sure it's not an internet. We also have different Wifi setups and cell towers.
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