Current PostgreSQL/PostGIS implementation always wants to connect to "postgres" database before showing the other databases on the server. Due to restrictions on "postgres" database or, as in my case, a connection pooler in front of the server that isn't configured to direct connections to "postgres" database to the actual database on the server, the connection is not possible. In other software as QGIS or pgAdmin, you can choose the database you want to connect to in advance, which means as soon you have credentials or configuration for this very datatabase, you can always connect to it. The current implementation may be practicable for small offices with few users but not for bigger/complex server infrastructure with many user roles where its quite unhandy to change credentials and configuration for databases like "postgres" that a never used in daily business.
