SMB automount seems to have major problems with multiuser mounts.
For the first logged in user, everything seems to be fine.
For every following logged in user, strange things will happen (e.g. firefox has problems showing the webdev console).
This reverts following commits:
- 9df6c93636 (Switch to systemd automount for /srv/samba/schools/default-school)
- f08c06d7a6 (krb5.conf from package krb5-user ist require)
14822ebb47