https://twitter.com/katyperry/status/1788352030857408565
So, Katy Perry is referencing the fact that fake AI photos of her at the Met Gala fashion show are fooling people on the internet, including apparently even her own mom. "Hold on to your common sense hat this fall" pretty clearly refers to how fake photos are gonna get used more and more in election season.
But check the comments, and it's all either bots or perhaps very dumb people, all rocking the blue checkmark since Twitter boosts those to the top of replies. Without the context, they have all parsed the tweet as being about Katy Perry's next fashion appearance or something.
Top replies since some people can't see:
https://gamefaqs.gamespot.com/a/forum/7/7e99bb77.jpg
It goes on like this
https://imgur.com/gallery/dXDmJHw
https://www.youtube.com/watch?v=75GL-BYZFfY