This GNOME Shell global menu and HUD implementation is not perfect, and you WILL find bugs. The Fildem global menu is set to automatically hide and only become visible on mouse over, but this can be changed, so you can have an always visible global menu if you want. Thanks to the HUD functionality (which is brought up by using the Alt + Space keyboard shortcut), you can also use this to search through the application menu, very useful for applications with vast menus, like GIMP for example. Using this, the menu that's usually built into the application window is displayed on the top GNOME Shell panel. This article explains how to install this on Debian / Ubuntu, Fedora and Arch Linux / Manjaro.
It was forked from the GNOME HUD project, and then made to also support adding a global menu to GNOME Shell. Fildem is a global menu and HUD for GNOME Shell.
