I’m trying to get into the boot menu of the Librem Mini (v1) with the preinstalled PureOS with Coreos/Seabios/PureBoot or how it’s called (i.e. the non-Heads version) as I want to install some other OS/distro from an USB drive.
However, I seem to be too slow.
At boot there is the rectangular static Purism logo for some time and it says at the bottom right:
ESC → Boot Menu
And indeed I succeeded once, but now I need to boot again and no matter how often I reboot and furiously press Esc (even when I see that exact screen), I cannot get it to get into the menu. The next screen I see is what seems to be the Linux kernel startup already where there is a loading/progress bar and Purisms logo as a text (this time) is animated at the end. Note that between these screens there is a slight delay without signal/a black screen.
This is really annoying and I guess the device just boots too fast.
My keyboard is connected via USB, so it should have no issues there and in GNOME etc. it also works.
Is there any less painful way then trying another 100 times?
Edit: Sometimes I managed to get into GRUB which (again with Esc) presents me with an unhelpful list of “OSes” to boot including PureOS of course and memcheck with different start-up parameters, as it seems.