XScreenSaver, Wayland and locking.
Welp, I got crickets in answer to my question, "How do I find the wl_surface backing an Xwayland X11 Window?" and that does not bode well for XScreenSaver ever being able to lock your screen on Wayland. The only...
https://jwz.org/b/ykrj
Welp. All that lovely "AI" derailment aside, we now have an answer:
It is literally impossible for XScreenSaver to lock the screen under Wayland. Cannot be done. None of the extant, spottily-supported "protocols" will allow the screen to be locked while an Xwayland surface is visible.
Great job, everybody. Perfect, no notes.
jwz
Cameron Bosch
Ozzelot 
Vicente Reyes
Patrick Morris Miller
lalala sombra