Docky trash docklet icon does not load on autostart

[Stuart Ludwig]

The trash docklet icon in Docky seems to be broken/not loading properly after log in.

How to reproduce:
Whenever Docky autostarts at login.

Steps to Reproduce:
1. Clean install of Xubuntu 18.04
2. Perform updates
3. Install Docky and its dependencies
4. Start Docky
5. Enter its configuration menu
6. Tick the "start when user logs in" checkbox if it's not already ticked
7. Restart or log out and log back in
8. Trash docklet icon is missing

Docky version: 2.2.1.1 Release

Distro: Xubuntu 18.04 LTS

Xfce Desktop Version: 4.12

X version number: 11.0

X.Org version: 1.19.6

Video Card: NVIDIA Corporation GP106 [GeForce GTX 1060 6GB]

Mono Version: Mono JIT compiler version 4.6.2 (Debian 4.6.2.7+dfsg-1ubuntu1)

Terminal outout:
[Info 07:58:34.655] Docky version: 2.2.1.1 Release
[Info 07:58:34.657] Kernel version: 4.15.0.20
[Info 07:58:34.657] CLR version: 4.0.30319.42000
[Debug 07:58:34.737] [UserArgs] BufferTime = 0
[Debug 07:58:34.737] [UserArgs] MaxSize = 2147483647
[Debug 07:58:34.737] [UserArgs] NetbookMode = False
[Debug 07:58:34.737] [UserArgs] NoPollCursor = False
[Error 07:58:34.743] [SystemService] Could not initialize power manager dbus: 'Could not load type 'Docky.Services.SystemService\+IUPowerProxy' from assembly 'DBus.Proxies, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' because it is implements the inaccessible interface 'Docky.Services.SystemService+IUPower'.'
[Info 07:58:34.744] [SystemService] at System.Reflection.Emit.TypeBuilder.CreateTypeInfo () [0x002dc] in <8f2c484307284b51944a1a13a14c0266>:0
  at System.Reflection.Emit.TypeBuilder.CreateType () [0x00000] in <8f2c484307284b51944a1a13a14c0266>:0
  at DBus.TypeImplementer.GetImplementation (System.Type declType) [0x000e3] in <91cfe10d2aa049c9af550645dbbec075>:0
  at DBus.BusObject.GetObject (DBus.Connection conn, System.String bus_name, DBus.ObjectPath object_path, System.Type declType) [0x00001] in <91cfe10d2aa049c9af550645dbbec075>:0
  at DBus.Connection.GetObject (System.Type type, System.String bus_name, DBus.ObjectPath path) [0x0002b] in <91cfe10d2aa049c9af550645dbbec075>:0
  at DBus.Connection.GetObject[T] (System.String bus_name, DBus.ObjectPath path) [0x00001] in <91cfe10d2aa049c9af550645dbbec075>:0
  at Docky.Services.SystemService.InitializeBattery () [0x00030] in <7cbfebdf01bd437fb1e0b3e770f0dbae>:0
[Error 07:58:34.746] [SystemService] Could not initialize Network Manager dbus: 'Could not load type 'Docky.Services.SystemService\+INetworkManagerProxy' from assembly 'DBus.Proxies, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' because it is implements the inaccessible interface 'Docky.Services.SystemService+INetworkManager'.'
[Info 07:58:34.747] [SystemService] at System.Reflection.Emit.TypeBuilder.CreateTypeInfo () [0x002dc] in <8f2c484307284b51944a1a13a14c0266>:0
  at System.Reflection.Emit.TypeBuilder.CreateType () [0x00000] in <8f2c484307284b51944a1a13a14c0266>:0
  at DBus.TypeImplementer.GetImplementation (System.Type declType) [0x000e3] in <91cfe10d2aa049c9af550645dbbec075>:0
  at DBus.BusObject.GetObject (DBus.Connection conn, System.String bus_name, DBus.ObjectPath object_path, System.Type declType) [0x00001] in <91cfe10d2aa049c9af550645dbbec075>:0
  at DBus.Connection.GetObject (System.Type type, System.String bus_name, DBus.ObjectPath path) [0x0002b] in <91cfe10d2aa049c9af550645dbbec075>:0
  at DBus.Connection.GetObject[T] (System.String bus_name, DBus.ObjectPath path) [0x00001] in <91cfe10d2aa049c9af550645dbbec075>:0
  at Docky.Services.SystemService.InitializeNetworkManager () [0x0005c] in <7cbfebdf01bd437fb1e0b3e770f0dbae>:0
[Info 07:58:34.751] [ThemeService] Setting theme: Classic
[Debug 07:58:34.755] [DesktopItemService] Loading remap file '/usr/share/docky/remaps.ini'.
[Debug 07:58:34.756] [DesktopItemService] Remapping 'Picasa3.exe' to 'picasa'.
[Debug 07:58:34.756] [DesktopItemService] Remapping 'nbexec' to 'netbeans'.
[Debug 07:58:34.756] [DesktopItemService] Remapping 'deja-dup-preferences' to 'deja-dup'.
[Debug 07:58:34.756] [DesktopItemService] Remapping 'VirtualBox' to 'virtualbox'.
[Debug 07:58:34.756] [DesktopItemService] Loading remap file '/home/xubuntu/.local/share/docky/remaps.ini'.
[Debug 07:58:34.756] [DesktopItemService] Remapping 'Picasa3.exe' to 'picasa'.
[Debug 07:58:34.756] [DesktopItemService] Remapping 'nbexec' to 'netbeans'.
[Debug 07:58:34.756] [DesktopItemService] Remapping 'deja-dup-preferences' to 'deja-dup'.
[Debug 07:58:34.756] [DesktopItemService] Remapping 'VirtualBox' to 'virtualbox'.
[Debug 07:58:34.756] [DesktopItemService] Loading desktop item cache '/home/xubuntu/.cache/docky/docky.desktop.C.UTF-8.cache'.
[Info 07:58:34.815] [DockServices] Dock services initialized.
[Debug 07:58:34.821] [DBusManager] DBus Registered: org.gnome.Docky
[Debug 07:58:34.822] [DBusManager] DBus Registered: net.launchpad.DockManager
[Debug 07:58:34.866] [PluginManager] Plugin manager initialized.
[Debug 07:58:34.869] [PluginManager] Processing config file for "Battery Monitor".
[Debug 07:58:34.884] [PluginManager] Processing config file for "Bookmarks".
[Debug 07:58:34.885] [PluginManager] Processing config file for "CPU Monitor".
[Debug 07:58:34.885] [PluginManager] Processing config file for "Clippy".
[Debug 07:58:34.885] [PluginManager] Processing config file for "Clock".
[Debug 07:58:34.885] [PluginManager] Processing config file for "Desktop".
[Debug 07:58:34.885] [PluginManager] Processing config file for "Gmail".
[Debug 07:58:34.885] [PluginManager] Processing config file for "Mounter".
[Debug 07:58:34.886] [PluginManager] Processing config file for "NPR".
[Debug 07:58:34.886] [PluginManager] Processing config file for "Network Manager".
[Debug 07:58:34.886] [PluginManager] Processing config file for "Network Monitor".
[Debug 07:58:34.886] [PluginManager] Processing config file for "Recent Documents".
[Debug 07:58:34.886] [PluginManager] Processing config file for "Session Manager".
[Debug 07:58:34.886] [PluginManager] Processing config file for "Timer".
[Debug 07:58:34.887] [PluginManager] Processing config file for "Trash".
[Debug 07:58:34.887] [PluginManager] Processing config file for "Weather".
[Debug 07:58:34.887] [PluginManager] Processing config file for "Workspace Switcher".
[Info 07:58:34.921] [PluginManager] Loaded "Trash".
[Debug 07:58:35.004] [GdkPixbuf] gdk_pixbuf_from_pixdata() called on:
[Debug 07:58:35.005] [GdkPixbuf] Encoding raw
[Debug 07:58:35.005] [GdkPixbuf] Dimensions: 16 x 16
[Debug 07:58:35.005] [GdkPixbuf] Rowstride: 64, Length: 1048
[Debug 07:58:35.005] [GdkPixbuf] Copy pixels == false
[Debug 07:58:35.005] [GdkPixbuf] gdk_pixbuf_from_pixdata() called on:
[Debug 07:58:35.005] [GdkPixbuf] Encoding raw
[Debug 07:58:35.005] [GdkPixbuf] Dimensions: 16 x 16
[Debug 07:58:35.005] [GdkPixbuf] Rowstride: 64, Length: 1048
[Debug 07:58:35.005] [GdkPixbuf] Copy pixels == false
[Debug 07:58:35.005] [GdkPixbuf] gdk_pixbuf_from_pixdata() called on:
[Debug 07:58:35.005] [GdkPixbuf] Encoding raw
[Debug 07:58:35.005] [GdkPixbuf] Dimensions: 16 x 16
[Debug 07:58:35.005] [GdkPixbuf] Rowstride: 64, Length: 1048
[Debug 07:58:35.005] [GdkPixbuf] Copy pixels == false
[Debug 07:58:35.005] [GdkPixbuf] gdk_pixbuf_from_pixdata() called on:
[Debug 07:58:35.005] [GdkPixbuf] Encoding raw
[Debug 07:58:35.005] [GdkPixbuf] Dimensions: 16 x 16
[Debug 07:58:35.005] [GdkPixbuf] Rowstride: 64, Length: 1048
[Debug 07:58:35.005] [GdkPixbuf] Copy pixels == false
[Debug 07:58:35.008] [GdkPixbuf] gdk_pixbuf_from_pixdata() called on:
[Debug 07:58:35.008] [GdkPixbuf] Encoding raw
[Debug 07:58:35.008] [GdkPixbuf] Dimensions: 16 x 16
[Debug 07:58:35.008] [GdkPixbuf] Rowstride: 64, Length: 1048
[Debug 07:58:35.008] [GdkPixbuf] Copy pixels == false
[Debug 07:58:35.008] [GdkPixbuf] gdk_pixbuf_from_pixdata() called on:
[Debug 07:58:35.008] [GdkPixbuf] Encoding raw
[Debug 07:58:35.008] [GdkPixbuf] Dimensions: 16 x 16
[Debug 07:58:35.008] [GdkPixbuf] Rowstride: 64, Length: 1048
[Debug 07:58:35.008] [GdkPixbuf] Copy pixels == false

[Javier Perales Gran (selarep)]

Also Xubuntu 18.04, and exactly the same issue.
I have solved it with a workaround:
- Run xfce4-session-settings in terminal.
- Autostartup tab.
- Edit Docky, and change docky by bash -c "sleep 1 && docky"

I don't know why this works, but it does.