87
edits
Changes
→Mozilla 17 (Firefox 17) or later
: Customizing default action of "wheel" event. The value 0 means "Do nothing", 1 means "Scroll contents", 2 means "Go back or forward in the history", 3 means "Zoom in or out the contents". You cannot specify different action to vertical wheel operation and horizontal wheel operation because both deltaX and deltaY values can be non-zero same time. So, specifying different action doesn't make sense.
Note that unlike 16 or earlier, you cannot specify the unit of delta values such as scrolling by pixel, line or page. I.e., you cannot specify the deltaMode value of DOM WheelEvent with any preferences. On Windows, the scroll unit is by line or page with mouse wheel. That depends on the system settings. On Mac, the scroll unit is by pixel or line. That depends on whether the device supports pixel scroll or not. On Linux, the scroll unit is always by line.
== Mozilla 16 (Firefox 16) or earlier ==
