I've got linux iso installed on a bootable usb and boot it from refind which works fine. But when I choose to install ubuntu in the grub menu I get a black screen.
After some digging online I read that I should add
nomodeset to a line in the grub editor (pressing e when seeing ubuntu options: try ubuntu, install ubuntu etc.) to keep these changes I must press f10. But of course this is impossible because of the touchbar. It also says you can press control+x but as I found out this doesn't work and just types the letter x (a known bug).
How do I get around this? I only have one usb slot and that is used to boot linux, so I can't plug in an external keyboard. I also tried changing the key mapping (tilde to f10) from the terminal but these changed mappings appear to only work when booted in macos.