In all seriousness, visiting the Louvre if you are in Paris has to be at the top of the list of places to visit.
Besides the Mona Lisa, the Venus De Milo and other incredibly famous works of art are on display, when I was there, they are all protected from idiots like these climate protestors, I still favor severe beatings these fools.
Actually, they could rig up a sprayer to spray red indelible ink at anyone throwing something at it. It would be easy to retrofit.
Bring back the stocks and they will go away...............