bug#74134: 29.4; emacs-pgtk and emacs-gtk-x11 does not react the same way to c-s-u

[Eli Zaretskii <eliz@gnu.org>]

> From: joakim@verona.se
> Date: Thu, 31 Oct 2024 13:19:40 +0100
> 
> 
> I would like to be able to enter unicode chars the same way you do in
> other applications under wayland or x11, using control shift u + 4 hex
> chars ret.
> 
> In emacs-pgtk it seems like c-s-u tries to do this, because a little U
> with underscore appears, same as in firefox, but then you cant type the
> hex code.
> 
> In emacs-gtk-x11, c-s-u works as advertized in the emacs manual at
> least, it runs universal-argument.
> 
> I would prefer it if c-s-u could be configuered to enter unicode same as
> in other applications, if possible.

Isn't this the following known issue from PROBLEMS?

  ** Certain keys such as 'C-S-u' are not reported correctly.

  Some keys with modifiers such as Shift and Control might not be
  reported correctly due to incorrectly written GTK input method
  modules.  This is known to happen to 'C-S-u' and 'C->', which are
  misreported as 'C-u' and '>'.

  To disable the use of GTK input methods, evaluate:

    (pgtk-use-im-context nil)

  This will also cause system input methods and features such as the
  Compose key to stop working.

  On X Windows, users should not use Emacs configured with PGTK, since
  this and many other problems do not exist on the regular X builds.