Comment by ac29

At least at the moment Librem5 still requires non-upstreamed drivers: "The kernel will be the 5.3 mainline kernel with some additional drivers" [0]

They do at least appear to be actively developing those drivers publicly for eventual submission upstream, though: https://source.puri.sm/Librem5/linux-next/activity

[0] https://developer.puri.sm/Librem5/Software_Reference.html