Event onBeforeDrop not triggered on Mac OS X

I’m using a dhtmlxTree object. it seems that event “onBeforeDrop” is not triggered on Mac OS X when the browser used is Firefox and when the Ctrl Key is pressed.

Works correctly with Chrome or Safari on OSX.

Works correctly with Firefox on a Windows 10 platform.

Works correctly with Firefox on MAC OSX with any other key (shitKey, alfKey, metaKey) than ctrlKey

I’m using a recent version (dhtmlxSuite 5.1.0)

ctrl + click on mac os opens the context menu on Mac OS. Could you please, clarify the purpose of using the dragging with the ctrl+click in your case.