E mini flash crash after hours

I just checked futures a few minutes ago and had to make sure this wasn't a glitch. The E mini futures had a flash crash this evening. If the market opens down here, it implies the SPY, which closed at 145.11 would have hit 139.1 and currently be trading at 141 and change.

There's no volume on after hours futures contract trading so this can all reverse tomorrow and we could close higher. However, this is a warning sign. I've been bearish this market and have been watching for an opportunity to really load up on some shorts but it hasn't materialized yet.

However, flash crashes after hours at market highs is just another signal that I'm watching closely.