I’m not even shown a menu where I can press anything
Like I said, it says “Welcome to GRUB!” and from there on nothing, nothing to choose from, nothing to type, no input of any kind works except for pressing the power button and shutting down the notebook.
RIght now (literally one minute ago) I tried creating a Live-USB with Linux Live USB Creator.
No at least the following happens:
Welcome to Grub!
error: unknown filesystem
Entering rescue mode...
That has never happened before though. Only now after using Linux Live USB Creator.
Thx for your answer, btw!
Edit: The USB pen is not GPT protected, I already checked that.