"uint8_t type unknown"

Auswahl_005

yet it does compile. How comes?

are you using arduino IDE

Arduino IDE 2.0 beta 6

does it is compiling or not

Take a look at the peek problem option,or add variables

which operating system is your's.

As I said: "yet it does compile". On Ubuntu 16.04.7 LTS

Just to add to the confusion:

It is a beta program so it may be a bug so report it to arduino community.