JavaScript must be enabled in order to use this site.Please enable JavaScript in your browser and refresh the page. Editing an event Double-click an event on the Timeline. The event opens in the Source Player. To edit, mark in and mark out the event on the Source Player. To edit on the Timeline, select an event on the Timeline and edit via Split, Trim Top, or Trim Tail buttons. The event duration automatically updates in the Timeline. There is no Undo feature for these operations. Parent topic: The Simple Editor tool