This must have been already solved with this update:
[ALPM] upgraded gnome-shell (1:48.0-1.1 -> 1:48.1-1.1)
Is your system fully updated?
extra/gnome-shell 1:48.1-1 (gnome) [installed: 1:48.1-1.1]
Next generation desktop shell
What says: pacman -Ss gnome-shell on your system?