Ubuntu Vibes posted a guide about installing Firefox Globalmenu in Ubuntu 11.04 Natty Narwahl

Now you can install global-menu for Firefox as an extension is in development that brings support for the browser in Ubuntu 11.04.

The extension is available in a PPA for Ubuntu 11.04 only and you require latest version of Firefox 4 - beta 9. To install the extension, run following commands in your terminal

  Install Firefox Globalmenu in Ubuntu 11.04 Natty Narwahl