This one's been around for long enough, at least since in early May. It's basic JavaScript bug so surely you guys can fix it.
Happens occasionally when I try to view the guild roster. The gateway stops responding and I need to refresh the page to log back in. The error:
DataTables warning (table id = 'gatewayTableGuildRoster'):
Requested unknown parameter '9' from the data source for row X.
Replace X with the number of people in your guild, minus one (array element counting from zero).
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