How can I change the `WM_CLASS` property of a Comp...

# compose-desktop

[Marcin Wisniowski]

How can I change the WM_CLASS property of a Compose window, as used by window managers / task managers on Linux?

[Marcin Wisniowski]

To answer myself: you can't and the 16 year old feature request in OpenJDK is unresolved: https://bugs.openjdk.org/browse/JDK-6528430

[Marcin Wisniowski]

However JetBrains IDE's manage to do it, I assume it's a functionality of the special JetBrains Runtime?

[ephemient]

https://github.com/JetBrains/intellij-community/blob/66eed4a49b5ed4b0064d6d287d7c5bb06bbefbd6/platform/platform-impl/src/com/intellij/platform/ide/bootstrap/ui.kt#L241

[Marcin Wisniowski]

Came here to post this and I see you actually found it earlier, nice.
I did do some experimentation and found you can have different WM_CLASS for different windows if you just do the above before opening each window.

[Zoff]

sorry i dont understand. how does that work in my app?

[Marcin Wisniowski]

If you don't already have a reason to need a specific WM_CLASS, then you probably don't need this.

[Zoff]

i think its needed for linux .desktop files so that the app isnt opened multiple times

[Marcin Wisniowski]

You don't need to change it though, just use the automatic one for that. You can use xprop WM_CLASS to find what it is on your app.

[Zoff]

WM_CLASS(STRING) = "MainKt", "MainKt"
thats Meh. because lockscreen notifications in ubuntu display as "MainKt" which kinda is not really nice.
(strangly enough normal notifications do display with a proper title)

[Marcin Wisniowski]

That’s weird, WM_CLASS is not supposed to be user visible.

[Marcin Wisniowski]

But yeah, you can change it with reflection.