Indeed, by default, snaps cannot access data outside of their directory.
Give the nextcloud snap access to /media:
sudo snap connect nextcloud:removable-media
After this, nextcloud can access data below /media.
Indeed, by default, snaps cannot access data outside of their directory.
Give the nextcloud snap access to /media:
sudo snap connect nextcloud:removable-media
After this, nextcloud can access data below /media.