[BusterDog]

“What is the flag emoji for an idiot. Just asking.”

*****

Like a happy face or thumbs up emjoi, but a country’s flag. Signals support of the new thing.

[Svartalfiar]

Signals support of the new thing.

Signals support of something, as long as you don't have to actually do anything about it in any concrete way. And, as you can see, is dumped as soon as the next big popular thing to "support" comes out!