Pinebook Pro no boot progress indication

[Strit]

That’s because as of kernel 5.13, we stopped patching in the unmaintained kernel bootsplash to our kernel.

To change to the currently used bootsplash (plymouth) see the guide in this post:

Manjaro ARM 21.02 released!

Manjaro ARM 21.02 released! We are proud to announce the release of Manjaro ARM 21.02, which will soon be available via manjaro.org. Currently we have download images for: Raspberry Pi 4, Rock Pi 4C, RockPro64, Khadas Vim 2, Khadas Vim 3, Odroid N2, Pinebook and the Pinebook Pro. Manjaro ARM is proud to be the default installation on the Pinebook Pro from Pine64. We have put in a lot of work to get to this point and we are excited that we have been accepted by the creators of this laptop, as …

To use plymouth, install plymouth and plymouth-theme-manjaro and add quiet splash plymouth.ignore-serial-consoles to your boot script instead of bootsplash.bootfile=bootsplash-themes/manjaro/bootsplash, then run sudo plymouth-set-default-theme -R materia-manjaro. You can then disable/uninstall the bootsplash stuff.
You may want to add your devices drm stuff to MODULES=() and plymouth after base and udev to HOOKS=() in /etc/mkinitcpio.conf.