Another necropost, but I think the above answer is wrong.
In both Xfce and Unity (but not Gnome) you can control what appears in the settings panel by adding to the
Categories in the
.desktop file for whatever utility you want to add.
I installed Xfce on regular Ubuntu 16.04, but noticed that the Settings panel in a live usb session of Xubuntu 16.04 was different. One thing missing in my setup was Language Support. I looked for Language Support (actually Tacaíocht Teanga in my case) in
/usr/share/applications with a root file manager and opened it in a text editor. I then changed the
All sections of the settings panel require:
- Xfce: Settings;X-XFCE-SettingsDialog
- Unity: Settings;X-Unity-Settings-Panel
- Xfce: X-XFCE-PersonalSettings
- Unity: X-GNOME-PersonalSettings
- Xfce: X-XFCE-HardwareSettings
- Unity: HardwareSettings
- Xfce: X-XFCE-SystemSettings
- Unity: X-GNOME-SystemSettings
- Xfce: If no section is specified the icon will appear in the Other section
- Unity: Much more complicated! If you look at standard Gnome/Unity Settings .desktop files they have extra lines giving a keyword that (I think) is used for localisation, e.g. for Language Support (language-selector.desktop)
If you add the name you want to appear to an
X-Unity-Settings-Panel= line, it will appear under Other. If you don’t include this line the Other section will appear but the icon will not. For other sections, it doesn’t matter if you include this or not.
Syntax: although you often see these lines ending in a semi-colon, it is only required to separate each category with a semi-colon.
In a GUI file manager
.desktop files appear with the
Name= field name as their filename, not their real filename. So to find the right file to edit from the command line you’d have to do something like…
sean@nung:/usr/share/applications$ grep "Language Support" *.desktop
sean@nung:/usr/share/applications$ sudo nano language-selector.desktop
Although it’s unlikely to happen very often, the .desktop files in
/usr/share/applications can be overwritten when an app is updated or the system is upgraded.
For Xfce the solution is simple: copy the files you want to change to
~/.local/share/applications and make your changes to those files. They will override the global ones.
For Unity it’s not so simple. To be added to the settings panel the file must exist in
/usr/share/applications. You can still move the files to
~/.local/share/applications (for ease of editing/storage) and link them back to
/usr/share/applications. The links will still potentially get blitzed, but you’ll still have your modified files to relink.
For Unity the local .desktop files need to be executable.