Several times now (most recently a few minutes ago) I have clicked the "mark all as read" button only to come back sometime later to find dozens or even hundreds of posts in the "posts you have not read" screen. These are definitely not unread posts, believe me I've checked. Some were most recently answered months or even years ago and should have been marked "read" the first time I clicked the "mark all as read" button.

It appears to be intermittent. Sometimes I will go for days without a problem then, as today, it happens several times over the course of an hour or two. I haven't been able to spot any kind of pattern, from what I can see it's just random.

This is probably not relevant to what you describe, but I noticed that threads I've already read become unread when a post in the thread is selected as "best answer" or a post in the thread is edited (e.g. to remove a contact detail or to fix formatting issues).
TanitThis is probably not relevant to what you describe
True, that kind of thing would account for, at most, maybe a dozen or two over the course of a few days. I'm talking about dozens to hundreds in a matter of just a few minutes in many cases.
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Hey guys! This is a bug we will try to fix as soon as possible. Emotion: wink