with the hope for a hint I subscribed to this list. Here is my issue:
After upgrading the Debian Box to Buster (within LibreOffice from 5.x to
22.214.171.124) some fonts are missing in LO while they are exisiting on the
system, an example is urw-gothic-l . I used to use that font in some
templates and cannot find the 'switch' to make LO use that system font
and make my templates usable again.