Happens if the user's `style ID` is not in the STYLES TABLE for whatever reason.
Then the error is triggered, we will provide an extra fallback prior of that error's check.. (which shouldn't never happen again).
@see https://www.phpbb.com/community/viewtopic.php?f=556&t=2521151
@see https://www.phpbb.com/community/viewtopic.php?p=15318346#p15318346