The code below is totally valid. Next in the code it checks category mods. It returns true if the global mod is turned on
Code:
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If you also look at the code where is_moderator is set that it is always contained inside an if clause that already has if user is admin or moderator access do this. It is not ran for normal users.
See look how it looks in the code
Code:
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I dont see anywhere anyone whom you have not set as having mod access can have mod access.