No access to directory "/config/postgres": Permission denied

[buchengasse]

2 weeks ago I installed abesnier/guacamole on a Raspberry Pi. It worked fine, I could access my Windows PC from my Macbook.

Today I redeployed the latest version. Now the container does not start any more. The error message in the log is:

postgres: could not access directory "/config/postgres": Permission denied

I deleted the /config folder and added
user: root
in the Docker-Compose file, but this did not help, I get the same error.

In Putty I can see, that the folder /config/guacamole has owner root, group users and rights rwxr-s---.
The folder /config/postgres, however, has owner messagebus, group render and rights rwx--S---.