Tootfinder

I have implemented a KDE-Wayland analogue of XKill called...wait for it...wkill. Usage is like you'd expect: you run it, you get a crosshair, you click on the window you want to kill, and it is killed.
Technical implementation is, in essence:
On click, send `zwlr_foreign_toplevel_handle_v1.close()` to the compositor (politely requesting the application to an hero).
Then, resolve the PID from `/proc` by matching `app_id`,, then send **SIGTERM** (or **SIGKILL** if launched…

Uh. Is this a known #ubuntu thing? Or is this a quirk of #Wayland?
Sometimes when I bring a window from the background it stays like this, text and icons all garbled. Sometimes if I resize or jiggle it, it sorts itself out, sometimes I have to kill it.