This is a huge escalation of events, Friday prayers are usually reserved to show the support the regime has, however, Iranians have used this event to voice their anger at the regime. They're chanting this slogan while waving their fists towards the mullah who's the representative of the supreme leader. They're essentially saying that the regime is their real enemy, and they're no longer going to fall for the regime's propaganda anymore.
Twitter: https://twitter.com/democraticiran3