Thanks for the thought, but I believe he is asking how to start pgAdmin4 without opening a browser window. In other words, start pgAdmin4 but *never* see a browser window until you choose "New pgAdmin 4 window ...".
I don't think that's possible, at least from the desktop variant of pgAdmin4. I would love to be shown to be wrong.
pgAdmin4 is still stuck between being a desktop application and a server application.