How to install Firefox extensions globally

Whether your building a PC to be imaged or you have a system used by many users, you can install your fav Firefox extension cocktail so all users get it. By default extensions are installed per user so we're going to change this behavior. I recommend that you first download FEBE which is an excellent Firefox profile backup extension. Once installed you will see a "quick backup" option under Tools\FEBE. Select all the extensions you want to export, define a destination path, and check the box to "create a single xpi". When you go to install your global extensions you'll only have to install 1 instead of 10. Once you have the combined xpi saved close out of Firefox completely and run this command from the cmd prompt in the program files\ firefox directory.

firefox.exe -install-global-extension "<path to xpi>"

You won't get any confirmation of success. To verify this completed successfully navigate to c:\program files\mozilla firefox\extensions. you should see a new folder called Multipack@febe.fx. Inside will be all of the individual xpi's and all users should now see them in their browsers.