If an app defines StartupWMClass use that to determine window icon (!6537) · Merge requests · Plasma / KWin

This is to ensure that kwin can find the desktop file for apps such as Slack & Spotify when running inside of a Flatpak.

Flatpak enforces that package names are unique, which means that they may not allign with the app_id or wmclass set by the app itself.

For example Spotify has an app_id of "spotify" but the Flatpak has the desktop file as "com.spotify.Client".

If an app defines StartupWMClass use that to determine window icon