@Icon: Modifier question

I want to use the @Icon: modifier to change the icon of a button depending on the state of the COPYFILTER Argument

I made a button to toggle the state but the icon doeasnt change. The .png paths are loaded with Ctrl-Click on the @icon: modifier.
What am I doing wrong?

Set COPYFILTER=Toggle
@icon:/desktopdir/Filter-Add-16(1).png, COPYFILTER=Off
@icon:/desktopdir/Filter-Add-16gr.png, COPYFILTER=On

Try "Toggle" instead of "On". Does it work then? (That's what the commands on the default toolbar use.)

I'd move them to the top of the command as well, although I haven't checked if it's required.

Yes, it works! Thank you @Leo!