I am new to this, so I apologize beforehand if it's not entirely kosher, but I have a proposed change to the Dockerfile entrypoint.sh to allow for configurable servers.json filename path.
The reasoning behind this is that I have a Kubernetes deployment of pgadmin where I build a ConfigMap sort of dynamically. I can make the file appear in /pgadmin4, but it removes the contents of the directory for me (helpful!). Instead, I put it into a separate directory and set a new environment variable that defaults to the old pathname (backwards-compatible!) but allows me to set a custom environment variable in my custom Helm chart for my deployment.
pgAdmin removes the content of the directory? I'm not sure how it would do that - it doesn't delete anything like that.
I would love to move back to the "official" pgadmin container.
Please raise a feature request at https://redmine.postgresql.org/projects/pgadmin4/issues/new and attach the patch (just use git diff against a checkout of the master branch). You can send the patch here, but we need the feature request in the tracker anyway, so it's probably easier to attach it there.