9/10 it's because they didn't update their Mods or even try disabling them first.
Then people who haven't bought the game yet think "OMG how could it still be that buggy after all this time?"
It would be nice if whenever someone selects a Flair tag with "Bug" in it, they'd get a popup or blurb telling them to update/disable their crappy Mods before posting.
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