Re: PGTK-related misconceptions

[Po Lu]

Trey Peacock <gpg@treypeacock.com> writes:

> It does not seem to be a requirement of GTK 3.2 or XKB to send virtual
> modifiers.

See https://docs.gtk.org/gdk3/flags.ModifierType.html, which says:

  Since 2.10, GDK recognizes which of the Meta, Super or Hyper keys are
  mapped to Mod2 - Mod5, and indicates this by setting GDK_SUPER_MASK,
  GDK_HYPER_MASK or GDK_META_MASK in the state field of key events.

> The only compositor I have come across that actually sends a virtual
> modifier is mutter/GNOME. Neither wlroots nor Weston, the Wayland
> reference implementation, send them. I'm unsure about Plasma, but I
> believe this highlights an issue with the development of pgtk, if it
> is meant to be targeted towards wayland users it should be tested
> against more than just one compositor.

I don't have any other compositor installed that I can actually start.
Users, such as you, are supposed to do that part of the job.

> The experience of a user updating Emacs and realizing a key is no longer
> recognized, without any notification or justification would also be a
> step backwards.

That is the price you pay when using the development version of Emacs.
The key wasn't intentionally disabled, so I cannot know those problems
exist until users like you report them.

Hopefully, those problems will no longer exist when Emacs 29.1 is
released.

> I have spoken with devs of wlroots & wayland over IRC and they seem to
> agree that it is not necessary. I don't mean to be adversarial but would
> be happy to see this change amended to incorporate the entirety of
> wayland compositors.

Wayland compositors do not send those virtual modifier masks.  GDK is
supposed to, and does it correctly when running on GNOME Shell, so the
bug either lies in GTK or the other Wayland compositors.