|User since||August 2, 2012|
|Number of add-ons developed||0 add-ons|
|Average rating of developer's add-ons||Not yet rated|
Rated 4 out of 5 stars
What GoWebFish said underneath.
But you also have to make sure the "On for All web Pages" function of Firebug is ticked(enabled) if it was disabled.
That triggered yslow to work after trying for the ... time