The tile should say all... But when an Xwayland window is active, and you hit super key + k in order to kill it it ends up killing weston (probably because the window manager for X is built into weston right now, and it's owned by weston)
(I was actually expecting that it would kill the xwayland server, but I bet most users would expect that it would kill the xwayland app...)
Hi. I've sent a fix to the ml:
This is committed and fixed. Thanks Tiago.