You can use off to stop firing a particular callback for an event:

        
              function doStuff() { // do stuff! }
object.on('stuff', doStuff);

object.trigger('stuff'); // doStuff will be called

// Unregister ONLY the doStuff callback
object.off('stuff', doStuff);
object.trigger('stuff'); // doStuff will NOT be called

If you don't pass a callback argument to off, ALL callbacks for the event will not be executed when the event fires. For example:

        
              let callback1 = function(){};
let callback2 = function(){};

object.on('stuff', callback1);
object.on('stuff', callback2);

object.trigger('stuff'); // callback1 and callback2 will be executed.

object.off('stuff');
object.trigger('stuff'); // callback1 and callback2 will not be executed!

Class RSVP.EventTarget