If you had the old glibc-locales package from the extra repo installed, the update to the new core package will need manual intervention:
sudo pacman -Syu glibc-locales --overwrite /usr/lib/locale/\*/\*
Assuming you read the [Stable Update 2023-10-09] announcement, you should have known this.
After that, you may (or may not) have to re-configure all of your custom shortkeys. Possibly, a reboot will be needed. Cheers.