The article is a little crap because it doesn't cover the background much and assumes you're already familiar. But this is definitely about masks:
Hogwarts Express reminded us 3 times that we are under surveillance and to keep our face masks on during the ride. The TM even pointed to the ceiling saying “we are watching, keep your mask on”
I don’t think this was for masks per se? Sounds like it’s to stop hufflepuffs having quickies en route...
The article is a little crap because it doesn't cover the background much and assumes you're already familiar. But this is definitely about masks:
It’s wdwnt - they’re SJWs and their accuracy goes without saying.