This is unrelated, but I was also confused about having to set up a membership for meta.mathoverflow separately from having a membership to regular mathoverflow. I just entered the same username and filled the thing out, but is there some reason for this?
Or is this technically not part of the same site?
MathOverflow runs on old StackExchange software and in the old system there was no separate meta site. So an independent forum was set up ("independent" technically, but run by the moderators of MO). That's why you need a separate login.
I was trying to go back to this discussion to fill in the folks who tried to help me on what my issue was, and I could find no link to the discussion I started.
There's a link to meta at the top of the MathOverflow page, next to the "how to ask" link. Were you back on the Maths-SX site again?
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