Currently the MongoDb Charts system databases are called
which collides with our app specific databases.
A solution could be to prefix them e.g. mongodb_charts_metadata.
The same issue we have with a standard MongoDB Database named config which was introduced in MongoDb 3.6 to store information about replicasets. This could also have the mongodb_ prefix.
So currently there is no way to distinguish a MongoDB internal database from a app-specific one.