Is it possible to launch an application on a existing remote session from the client command line?

[jzyrobert]

So the setup is:
Remote: Ubuntu 22 running Xpra 4.4.3, with xpra start :100
Client: Windows 10 running Xpra 4.4.3, using Xpra attach ssh://<host>/100 to connect

Then, how can I start an application (e.g. xterm) from the windows client without restarting the connection?
If I run Xpra attach ssh://host/100 --start=xterm again, it works but restarts the connection so all existing windows are reloaded and get moved
I could either:

• Start xterm from the xpra system tray
• Open a SSH terminal with $DISPLAY=100 set and run xterm there

But I would prefer if I could do it from Windows powershell directly, basically a command line equivalent of launching something from the system tray.
I've looked through the man xpra documentation as well as the docs/ folder and the Wiki but could not see any obvious command to achieve this.

Thanks

[totaam]

From your xpra system tray, there should be a start menu.
With versions older than 4.4.4 (not yet released), you may need this patch on Ubuntu: a42e234

Alternatively, you can use xpra control:

• directly on the server: xpra control :100 start xterm
• from your client: Xpra_cmd control ssh://host/100 start xterm

[jzyrobert]

control start is exactly what I am looking for, thanks!