Thank you for your fast answer!
I’m using Android 10
It happens on every app that shows (complex) graphics. Like google Photos, Chrome, Whatsapp (If someone sends a video or photo), google maps (only in the “satellite” mode). It also happens on the camera sometimes.
I do use a SD Card and I had some issues with it before. My camera is saying, there wouldn’t be enough space on the card to take new photos. But on the settings it says the card is only about 50% full. I’m not sure, what the card is formatted, I guess it is internal