I can't get the ssh tunnel configuration that I use with pgAdmin3 to work with 4. After I enter the parameters and click "Save" I immediately get a dialog box that says:
Connection to the SSH Tunnel for host 'my-postgres-server' has been lost. Reconnect to the database server.
I'm using identity file authentication. In pgAdmin3 it wants both the private and public key files. In pgAdmin4 only the private file is specified. Otherwise everything is the same.
The error is instantaneous and the server is 1000 miles away, so it's not even waiting for a tunnel to get opened or a database connection to be attempted.
You are creating the ssh tunnel using same machine or there is some another machine in between?
If it's another machine, have you append the public key to the "authorized_keys" file?
Can you please provide logs and screenshot of the server dialog with ssh tunnel settings (if possible). To enable logging, ref: https://www.pgadmin.org/faq/#8