If like me you spend a lot of time reading, reviewing, navigating into W3C specs, you have probably also spent a lot of time scrolling to find the table of contents of these documents. Again, again and again. So many times you're probably fed up with it, like I am. In that case, this add-on for Firefox is for you. Install it and browse your favorite W3C spec. When it's loaded, look for the small box in the top-left corner. Make your mouse pointer hover over it to open the floating table of contents. Click anywhere (including on a link) in the expanded box to shrink it back. Enjoy :-)

Update: v1.1 is here. Next updates will be automatic.