I still believe that Indonesia does not officially recognize regional flags. Keep in mind, even Wikipedia can have mistakes and unchecked information.

Believe it or not, I have seen this today, but not in real life, because in 2016, I lived in Bogor, not Bandung.

What was this event?

Check it here

I guess I wouldn’t mind if you removed that they are unofficial, maybe ask @EuropeanV first

I will ask him, but it's night already (around 7PM) and I had to sleep.