I'm not sure, but I think there is some strange behaviour with notifications on the forum. I get the impression that, on a few occasions, there are notifications that I have either marked as read or outright "deleted", that appear in the list again later. Sometimes, if not during the same session, then after a subsequent log-in. Has anyone else noticed this?
I haven't really paid close attention, but that was my impression more than once. To convince myself that I'm not imagining things, I am even thinking of collecting screenshots of the notification panel, so that I can compare later. If I'm right, the team developing this platform should pay attention to how they manipulate their database; similar mistakes could lead to much thornier security or reliability problems.