A while back I wrote about TopMenu, a panel plugin that provides global menu (AppMenu) support for MATE, then also included support for Xfce and LXDE.

Here's where Vala Panel AppMenu comes in.

Vala Panel AppMenu is a global menu panel applet for Xfce, MATE and Vala panels, which uses unity-gtk-module as its backend, and it works with all the applications supported by Unity's AppMenu.

TopMenu (a global menu for MATE, Xfce and LXDE panels) is available in the official Ubuntu 16.04 repositories and it works great in Ubuntu MATE 16.04, but it doesn't work in Xubuntu 16.04 and Lubuntu 16.04 by simply installing the panel applet package.

Here's how to get TopMenu to work in Xubuntu 16.04 and Lubuntu 16.04, using the official packages, with a minor tweak.

Starting with Ubuntu 15.04, JAyatana was installed by default and it was configured to allow all Java Swing applications to use Ubuntu's global menu and HUD. This was changed yesterday when JAyatana was updated to no longer export the JAVA_TOOL_OPTION session file, meaning that Ubuntu no longer supports HUD or global menu for Java Swing applications by default.

This change affects both Ubuntu 15.10 and 15.04 (though for Ubuntu 15.04, this update is still in the proposed repository).

Global Application Menu is a Cinnamon (the desktop environment used by default in Linux Mint Cinnamon edition) applet which allows displaying the application menu on the Cinnamon panel, either as a horizontal menu or as a menu button:

Update: With just 3 days before the Ubuntu 15.04 release, Unity was updated with only one change: the default out of the box menu was set back to global menu.

After getting an option to always show the menus as well as global menu (Appmenu) support for Java Swing applications, yet another menu-related change has landed in Ubuntu 15.04 Vivid Vervet: locally integrated menu (LIM) is now the default menu.

You may also want to see: Alternative Global Menu For MATE And Xfce: Vala Panel AppMenu [PPA]

Update: for Xubuntu 16.04, see the following article: How To Get A Global Menu In Xubuntu 16.04 Or Lubuntu 16.04 (Using TopMenu)

Remember TopMenu? It's a standalone global menu which until recently only shipped with a MATE panel applet. Well, the TopMenu developer has added a new plugin, which allows using TopMenu under Xfce (Xfce Panel).

As you probably know, in the current stable Ubuntu releases (12.04, 14.04 and 14.10), the Unity (global) menus are displayed on mouseover for both the default menu that's displayed on the top Unity panel and LIM (locally integrated menu), which is displayed in the application titlebar.

With Ubuntu 15.04, there's a new option (not enabled by default) which allows setting the Unity menus to always be visible: