fires before the user presses the 'CTRL+V' keyboard command
| isCopy | boolean | indicates whether the event was copied or cut before pasting. The true value 'says' that the event was copied | 
| pasted_ev | object | the object of the new data item (the event that is created after pasting) | 
| original_ev | object | the object of the original data item (the event that was copied/cut) | 
| boolean | defines whether the default action of the event will be triggered (true) or canceled (false) | 
scheduler.attachEvent("onBeforeEventPasted", function(isCopy,pasted_ev,original_ev) {
    // here you can modify `pastedEvent`
    return true; 
});
The 'keyboard navigation' extension should be enabled.