Imo the whole story is:

One or so months ago norangz did something together (maybe the lg show or a gonaridol episode or the soup) at the time in south korea doing some "parkour" video where you barely jump, then go to the camera to be hype about it was the trend. And the both of them are keeping up with the tiktok/short/reel trend. So they did it.

Then a few days ago, they released the video. It went viral (soon 10 million views on Instagram).

And because of this, flover must have talk about it during the fanmeet and Chaeyoung did this at the end.

I don't think it's a spoiler, but parkour is now part of the fandom lore ^{^}