Love it! but do not work in FF14 Rated 5 out of 5 stars

I installed FF14.01 again... Firebug 1.10.0 and the latest Yslow 3.1.3.... Icon is there... but when I click on Yslow... see nothing... gray bar... and left Run Yslow and close... but that's it...

Problem solved: deinstall Yslow and then Firebug, restarted FF. Installed Firebug, the Yslow, restarted FF again.
Then I had the same problem: I opened Yslow... gray bar... clicked on the Firebug icon... and then suddenly the
Yslow appeared in the bar of Firebug again... closed the Yslow gray bar... and now its works as usual...

This review is for a previous version of the add-on (3.1.3). 

Tested same config on Win7 and Mac OS X 10.7.4 and it works

Can you please give me more details about your environment?