Bug#1077287: libgtk-4-1 v4.14: missing dependency on libgles2 (maybe there are alternatives) on at least i386

[Simon McVittie]

Package: libgtk-4-1
Version: 4.14.4+ds-3
Severity: serious
Justification: a maintainer says so
Tags: experimental
Control: block 1072395 by -1

While investigating test failures on i386, I tried installing
gtk-4-examples:i386 and its mandatory dependencies onto an amd64 GNOME
unstable system to assess whether the test failures reflect a serious
problem with applications or are ignorable.

(Full disclosure: I was actually testing with a prerelease of 4.14.4+ds-4;
but I suspect that 4.14.4+ds-3 has the same problem, and anyway it
definitely has other RC bugs.)

When I run gtk4-widget-factory, I get:

> Couldn't open libGLESv2.so.2: libGLESv2.so.2: cannot open shared object file: No such file or directory
> zsh: IOT instruction  gtk4-widget-factory

After installing libgles2:i386, gtk4-widget-factory runs successfully
and seems to work OK.

I already had libegl1:i386, libgl1:i386 and mesa-vulkan-drivers:i386
installed, so those are presumably not sufficient; but perhaps I was
missing some other related package that made "big GL" or Vulkan backends
not work?

Or maybe libgtk-4-1 needs to depend on libgles2, either on some or all
architectures?

I have not kept up with the status of which backend is used under which
circumstances, so I don't know the correct solution.

On the affected test system I'm using GNOME in Wayland mode on an Intel
GPU, if it matters.

    smcv