[bug#45062] [PATCH 1/2] gnu: xfce4-session: Fix xfce4-panel plugin detection.

[宋文武 <iyzsong@outlook.com>]

Kei Kebreau <kkebreau@posteo.net> writes:

> * gnu/packages/xfce.scm (xfce4-session)[source]: Add patch to append the path
> to user-installed xfce4-panel plugins to the X_XFCE4_LIB_DIRS environment
> variable.
> [...]
> +Ensure that xfce4 panel plugins in the user's Guix profile can
> +be found in the directories specified in X_XFCE4_LIB_DIRS.
> +
> +Partially fixes Guix bug #44916:
> +https://debbugs.gnu.org/cgi/bugreport.cgi?bug=44916.
>

Quote from #44916:
>> Aside from that, it seems like Xfce, when installed as a system-wide
>> desktop environment, does not look in the user's Guix profile for
>> plugins.  Panel modules are located by Xfce in the directories listed in
>> the X_XFCE4_LIB_DIRS environment variable.  For my Xfce configuration,
>> X_XFCE4_LIB_DIRS contains only /run/current-system/profile/lib/xfce4.

I think mix plugins from system and user profiles is a bad idea, the
system profile tend to be updated less than the user profile, so there
maybe some ABI problems between the xfce-panel in the system profile and
its plugins in the user profile due to mismatched versions.  

Does install both ‘xfce4-panel’ and ‘xfce4-whiskermenu-plugin’ into the
user profile works (hopeful a system xfce4 session will first pickup a
user installed xfce4-panel)?