booting pmOS should not fail if unable to mount the boot partition
On installs where the boot partition is mounted in the rootfs, booting pmOS shouldn't fail if it cannot be mounted. I was stuck debugging the bug fixed in !5764 (merged) for over half a day because systemd couldn't find the boot partition and it was stopping in "emergency mode", which was impossible to interact with on the device I was using (OP6). If I had been able to get access to a running rootfs, I could have figured out the bug a looooot faster.
To make mounting /boot less exciting, I think we can use nobootwait in fstab, to instruct mount to not block booting. I don't know if this also works with systemd, so some investigation is needed there.
Some distros only mount /boot on demand, like during a kernel update. This might be tricky to get right, but has some additional benefits. Could maybe be implemented by using an apk kernel hook to mount /boot if it's not mounted?