I apologize for the delay with reply to your problem.
Unfortunately this is the expected behavior as dhtmlxGrid may redefine such events.
It is recommended to use the dhtmlxEvent structure. It guarantees that the events won’t get lost:
dhtmlxEvent(document.body, “mousemove”, function(){ console.log(‘mouseMove’); });
dhtmlxEvent(document.body, “mouseup”, function(){ console.log(‘mouseUp’); });
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