In fairness to the commies, the one shown they claim did not go off. They decided to engage in some "street IED disposal" and take it apart for the camera which is some brilliant judgement on their part.
Here's a webm from the pol thread with a different view of it, no sound, but some weirdo tactical manspreads by on the right as it goes off.
Still, bit of a flash, a distinct bang (as per the earlier video with sound), and a lot of smoke, the latter of which screams black powder to me, in line with what the disassembled one allegedly contained.
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