The group administration is no longer included in the Community Edition from version 14.1 onwards.
For “old users”, i. e. those who have sent the statistics for a longer period of time up to and including version 1.8, the user administration will continue to be provided.
Read also:
Group administration for long time CE users
and
Group administration for 1.8 CE in 14.1
or for a 19.1 docker installation:
The repo is entered on the host with the access data and the package egroupware-epl-groups must be installed. This is then passed on to the docker container.