bug#60711: Compose fails to generate ≤ and ≥ (only those two! and only in emacs!)

[Marcin Kasperski]

I heavily use compose sequences while writing („CapsLock - >” – and I
get nice  „→”).

Since some recent emacs update (version below):

a) I can no longer generate ≤ and ≥ in Emacs

    All combinations (Compose >=, Compose >_, Compose _>) end the same:
    - after entering Compose > there is floating window hinting ≥
    - once I type =, puff, no character in the buffer, nothing.

b) Other Compose combinations I tried work.

    In particular Compose => works in Emacs and generates ⇒,
    Compose > > makes », Compose - > makes → and so on

    (can't guarantee everything works  but from dozens of combinations
    I use I found only those two to be problematic).

c) In all other applications ≥ and ≤ are properly generated with compose
    (tried gedit, terminator, firefox, vscode …)

So, for example, pressing
      a Compose < = b Compose < < c
in gedit/code/firefox results in
      a≤b«c
while in Emacs results in
      ab«c
(and really that, I tried saving file and hex-inspecting it, no
invisible character there).


Problem appeared after some recent update (most likely after I upgraded
to emacs 28 but I am not 100% sure, could be also related to Ubuntu
upgrade).

Problem reproduces in `emacs -Q`

Version I use now:

GNU Emacs 28.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.20,
cairo version 1.16.0)
 of 2022-05-31

(Ubuntu 22.04.1 LTS,
 emacs from ppa https://launchpad.net/~kelleyk/+archive/ubuntu/emacs,
 KDE Plasma as window manager)