Just today I had a reply to one of my comments, the notification popped up while I was browsing, but when I went to read it the reply itself had a timestamp of two hours prior. It's possible that this has happened before, but it was the first one that I noticed. Maybe more usage is lagging propagation, especially if the timing seems to be roughly the same amount.
I just realized this might not be seen for a bit if that's true, lol.
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