One case:
https://www.euronews.com/2019/05/02/french-government-claims...
There were others, but I'm too lazy to search. I remember seeing one other at least. Never seen any fake news problem with yellow vest. Usually Lemonde is prompt to denounce them.
That's just outright laughable.
Here's a 20 page report detailing how the yellow vest groups have been flooded by fake news, presumably by foreign agents.
https://avaazimages.avaaz.org/Report%20Yellow%20Vests%20FINA...
You can be sure where ever there's angry people in the world Russia will be there to help fan the flames.