No, didn't miss it at all.
ACAB is a skinhead thing.
https://www.adl.org/education/references/hate-symbols/acab
Note I don't adhere to ACAB; not all cops are bastards, just like not all cops are racists, homophobes, assholes, etc. I do however think there are bad cops who keep fucking things up for the good cops out there and that needs to be resolved.
That there's the hammer and sickle on this suggests either this guy is a fuckhead, or he's a Skinhead Communist(?).
Either way, there's no proof these are ANTIFA. Again, keep pushing the narrative though.