I have no idea what happens in France now, but in the past of many other countries the main place where the violent protests were really organized was not on any Social/IM platforms, even in the cases where it appeared to be so, but at the police/secret police/government HQs, where covert agents were prepared for triggering and/or leading violent actions during the protests, in order to discredit the peaceful demonstrators and enable direct action of the police against them.

Nowadays whenever you see "violent protests" and "destructions of private property by vandals during protests" you can never be certain whether they are organized by people who are against the government or by the government itself.