The fact there is still internet on and social media active is interesting in and of itself. Usually the regime would have turned everything off by now.

What was the spark this time? The water shortage?

Inflation, economy, everything. Iran has a seriously dysfunctional government and a lot of people are pissed off as to how much money they have pissed away building up a bunch of relatively useless missiles and missile bases when they could have spent it on infrastructure for the population. The government is openly talking about evacuating the entirety of Tehran due to infrastructure mismanagement. It's insane.