New issue by ProjectMoon on void-packages repository

https://github.com/void-linux/void-packages/issues/21766

Description:
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### System

* xuname:  Void 5.4.39_1 x86_64 GenuineIntel uptodate rrFFFFFF
  *output of ``xuname`` (part of xtools)*
* package:  plasma-workspace
  *affected package(s) including the version*

### Expected behavior
When starting Plasma X11 session from SDDM (or another login manager, probably), tray icons and dbus notifications work properly. The `DBUS_SESSION_BUS_ADDRESS` environment variable should be defined.

### Actual behavior
Tray icons do not work consistently, particularly for electron applications. dbus notifications from these applications are not received. `DBUS_SESSION_BUS_ADDRESS` is not defined.

### Steps to reproduce the behavior
Log in with Plasma X11, start an electron app like Riot or Signal. No tray icon or notifications appear. At best, the taskbar icons will light up. Executing `echo $DBUS_SESSION_BUS_ADDRESS` or similar in the terminal will produce no result.

I fixed this by adding `dbus-run-session` at the front of the `Exec=` line of `/usr/share/xsessions/plasma.desktop`. This mimics the setup of `/usr/share/wayland-sessions/plasmawayland.desktop`, and makes the tray icon and notifications work again.