This information from the thread Manjaro ARM Beta27 with Phosh (PinePhone / PinePhonePro) :
may be worth mentioning here.
In other words: Owners of the PinePhone Pro (i.e., not the original PinePhone, which uses the original megapixels package) will probably want to sudo pacman -S megapixels-ppp, in order to get Megapixels to recognize their camera. (This applies independently of the edition, since Megapixels is used on all GUI environments.)
The package was added by this update, as shown in the list below: