Recently I decided to start playing with Firefox extensions, and I needed to create a DEV profile for myself.
As usual I googled and found a good article on lifehacker by Gina Trapani, I read it. I followed the steps mentioned and I realized that it is not working.
After some tinkering and guess work I found that article had one crucial step missing(may be not as article is almost year old, and things may have changed since).
So I thought I will quickly write those steps down, for every one.