When installing a new distro from a USB key, there's always the somewhat hacky process of changing the boot order in order to boot from the USB drive instead of the internal drive. On most laptops this is done by pressing an F key (often F2 or F11) during the first few split seconds after pressing the power button, and then changing the order in the BIOS.
On Librems, this is done by pressing the ESC key, which I only discovered by asking a friend who has a Librem (after trying different F keys for quite a while, skimming the user manual, and searching for a solution to the problem online). This is obviously not a great situation, as many of our users probably install distros from live USB keys.
From a UX point of view, it would be ideal to detect if a bootable USB drive is plugged in, and go to the boot device selection menu directly, without pressing some secret key. But at a minimum we should provide users with the information what key is required to change the boot order somewhere in the OS and the manual that comes with the laptop.