I also have issues with the memberlist on the right side. Difference is for me that people do occasionally show up, but wrong. Sometimes they disappear, sometimes they appear correctly, sometimes they appear offline but with a green light as they are in fact online.
I noticed that after I posted this I also have the same issues you got, but some roles I can give to myself and it will show me in that specific role but it just shows the members as offline 2 but I can only see one offline but there is two
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Comment by @Duckisdaebest