Yes (1)No (3)
when used in a topic that is checked a lot (in my experience.) it will unfollow it for no apparent reason.
it has happened in topics I do not check often. but it's not as consistent.
Does it only happen in topics you've started? In topics you've replied to? In topics you haven't replied to? Things like that can all help.
It happens in TF: Alignment a lot, that's a topic I was very active in for quite a while. but has only happened In Bionicle Fighter once... I think. I'm not there nearly as often.
Back when I did use the mobile site, it was a common occurrence. Usually the topic would unfollow right after I posted.
like I said, it really only happened in alignment and I would typically have that open for days and just shut my laptop when I wasn't actively playing.
i'm going to say it's fixed.