How can I make Firefox use addons for multiple profiles?

Question

I created a new profile on firefox for testing reasons. I notice no addons except Skype is on it.

How do i set up addons to work across profiles?

I have about 10 and I'd rather not download them again for every profile.

Answer 1

Basically you need to download the .xpi for the extension you want to install. Then run the following command:

\path\to\firefox -install-global-extension \path\to\extension.xpi

I don't know if you can make already installed extensions global after they are installed. Perhaps a combination of this approach with @ChrisF's answer would solve that problem.

Answer 2

Would the FEBE extension be of any use?

It's primarily for backing up and restoring profiles, but it states:

Now you can easily synchronize your office and home browsers.

so I would have thought that you can synchronise different profiles on the same computer as well.