Subject: bug#44204: Emacs --with-xwidgets complains under Ubuntu 20.04

From: Po Lu <[email-masked]>
Date: Sun, 12 Dec 2021 18:56:01 +0800

Paul Eggert <[email-masked]> writes:

> On my Ubuntu 20.04.3 LTS x86-64 platform, where I observe both the
> above issues and the Gdk-WARNINGs I mentioned previously, 'dpkg -s
> libwebkit2gtk-4.0-37' reports:
>
> Version: 2.34.1-0ubuntu0.20.04.1
>
> and "env | grep '^XDG' | sort" outputs:
>
> XDG_CONFIG_DIRS=/etc/xdg/xdg-ubuntu:/etc/xdg
> XDG_CURRENT_DESKTOP=ubuntu:GNOME
> XDG_DATA_DIRS=/usr/share/ubuntu:/usr/local/share/:/usr/share/:/var/lib/snapd/desktop
> XDG_MENU_PREFIX=gnome-
> XDG_RUNTIME_DIR=/run/user/1000
> XDG_SESSION_CLASS=user
> XDG_SESSION_DESKTOP=ubuntu
> XDG_SESSION_TYPE=x11

Could you please install the debug information and source packages for
GDK 3 on that Ubuntu system, run Emacs under GDB with
`G_DEBUG=fatal-warnings', trigger the warning, and then print a
backtrace?

I want to know what is calling `gdk_x11_window_get_xid', and if it is
being called on the offscreen window.

Thanks.