A window mapped but left unpainted, or stale after a workspace switch, is a known failure of picom's glx
backend with damage tracking on some drivers, and the first suspect for the empty calendar reminder on
the workstation. Research 037 already found the backend to depend on the machine's driver. Both become
preferences whose defaults are today's (glx, use-damage true), so nothing changes until a machine is
given xrender or use-damage false to test it.
Owns its configuration, moved to picom's window rules; started once from the
session's xinitrc slot; Go tools restart, rules, window-opacity and toggle, which
find the operator's X session from the window manager's environment.
jschoubben
jochen