I've heard this thrown around, but I thought it was for upvoting posts that are later removed for violating Reddit's rules - not just upvoting any posts on quarantined subreddits.

I can't figure out if this is the case, though, here is what Reddit said, I think:

> Users who consistently upvote policy-breaking content within quarantined communities will receive automated warnings, followed by further consequences like a temporary or permanent suspension.