I recently bought a Librem 14 with PureBoot and a Librem Key. My typical setup boots to a VT console rather than GUI. I’d like to try this with the Librem, which I assume would be as simple as adding a menuentry option under /etc/grub.d/ with systemd.unit=multi-user.target, but I’ve no experience with PureBoot or Heads and wanted to check whether there might be any caveats I should know about :3
Has anyone tried this? My plan would be to basically follow the steps laid out here: https://askubuntu.com/a/1029350
Probably by PureBoot you mean PureOS, at least in some occurrences in your post. (PureBoot is the boot firmware, whereas PureOS is the Debian-family Linux distro, operating system.)
If you can find Debian instructions, they may be slightly better than Ubuntu instructions - although there’s a good chance the latter would work equally. I would definitely read the comments along with using it for the overall approach because the comments highlight some of the challenges.
My plan would be: you image the drive, you try whatever you can, and if it doesn’t work out you restore the drive. 