Command to close gahshomar window to tray

Hello people
I have an application ‘gahshomar’. After executing this application it will open a window and create a new icon as system toolbar (try menu)
What is the command to make open the application but close the window immediately so I have only the icon on the toolbar?

Don’t know, perhaps start on the website:

Topic title edited.

you use Manjaro KDE, so open kwin rule for this app (app system menu) and set start minimized

I no longer use KDE. It’s XFCE right now
I didn’t say I want to set the window ‘minimized’.
I want the window ‘closed’