The liberating role social networks played during the Arab Spring and the Russian protests of 2011 and 2012 was widely lauded. Little of that enthusiasm is on display today amid the violent "yellow vest" protests in France - even though Facebook is still doing what it does best: let people channel their rage.

In a 2011 paean to the "Facebook revolution", Mr Chris Taylor of tech news website Mashable wrote that Facebook was "democracy in action". Dr Philip Howard of the University of Washington, who researched the social network's role in the Arab Spring, said the same year that social media "carried a cascade of messages about freedom and democracy across North Africa and the Middle East and helped raise expectations for the success of political uprising".