More specifically, as it seems here: Some posts end up in notifications as being direct replies even while they don't quote / mention me. Some posts do quote me but I don't see a notification on that. Some seem to somehow (thread- and content-wise) refer to earlier posts of mine but neither mention me nor end up in a notification. And for the other sidelines of the thread, it's pretty much a couple of particular responses to "unknown parent" posts even though the parent posts on their source systems are apparently public. And now I wonder to write a bug report for "the Fediverse" as I'm totally unsure which of the systems involved is responsible for that and to which degree.