The Members tab seems to only list the most recent members. I don't know if this is a bug or not but I would expect to get a list of all members on the server. Since the members list in the right panel doesn't seem to be working as intended, and seem to only randomly list some members every now and then, there is no real or practical way to know exactly which members currently occupy the server.
Eveyone Seems to have the same issue regarding the list in servers
I think we all got same issue but just gets diff outcomes
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Comment by @Duckisdaebest