Ok so when I got my laptop it came with a leaflet stating that charging over USB-C was not possibly and should not be tried. So that was kind of a bummer, but I figured it would not cause me too much trouble.
Today I was browsing the Slimbook website when I stumbled upon a small note that the PROX supports charging over USB-C. So now I was confused. I went back to the drawer where I stored the leaflet to check the comment about not charging. So yes, it was surely there.
Then I figured I would live dangerously and I just plugged in a charger in the USB-C .... and ... it did not fry, it started charging. %confused%.
Today I was still looking around on the Internet when I stumbled upon the following remark and response on the Slimbook forum: