AFter full system update, on reboot sddm freezes

Hi @powernub, and welcome!

Try logging into the TTY and running/updating/syncing with pamac.

sudo pamac checkupdates && sudo pamac update -a

I don’t know if it’ll work or not, but it might, since pamac is Manjaro-orientated and contains a lot of customizations for Manjaro. See: Why pamac over pacman?