Hello! I've found that UPDATESTARTUPTTY command is passing only DISPLAY and GPG_TTY variables to pinentry, but pinentry-qt, pinentry-gnome, and maybe others supports Wayland, so it would be helpful to pass also WAYLAND_DISPLAY variable, for a case if more than one Wayland compositor is used.

I've added { "WAYLAND_DISPLAY" } to stdenvnames, and it worked perfectly.