>>160
こんな感じだったかな?
// Tab scrolling and select.
gBrowser.mTabContainer.addEventListener("DOMMouseScroll", function(event){
var DOWN_SCROLLS_MOVING_TO = 1; // LEFT: 1 RIGHT: -1
// event.detail is negative
this.advanceSelectedTab( (event.detail < 0) ? DOWN_SCROLLS_MOVING_TO :
-1 * DOWN_SCROLLS_MOVING_TO, true );
event.stopPropagation();
}, true);