Comment by spellcard199

Under Wayland with Gnome (it's gnome-specific), I recently learned you can kill windows by using Looking Glass:

  // 1. Open looking glass: Alt+F2 > lg
  // 2. Use picker to pick window (button on the top left corner).
  // 3. Now an object r(0) of type MetaSurfaceActor is available in the
  //    gjs console (or some other number if you've already used it).

  // To get pid:

  r(0).get_parent().get_parent().get_meta_window().get_pid()

  // To kill window and process:
  
  r(0).get_parent().get_parent().get_meta_window().kill()

Reference for what those .get_parent() refer to: https://gitlab.gnome.org/GNOME/mutter/-/tree/fc1de744/src/co...