@nebulon I can reproduce it on 2 of the 3 FreeScout instances, all three have at least LDAP:
The one with only LDAP shows indeed the translations for LDAP
FreeScout number 2 has: Block External Images, Custom Folders, Followers, LDAP Integration, Spam Filter, Tags
FreeScout number 3 has: Block External Images, Followers, LDAP Integration, Spam Filter, Tags, Two-Factor Authentication
I have a gut feeling it has to do with Block External Images, since I bought and installed it on 2 of the 3, those 2 have the issue.