Receive mousemove events from iframe, too

You should look through combining parent document event binding with document.getElementById('iFrameId').contentDocument event, witch allows you to get access to iFrame content elements.

https://stackoverflow.com/a/38442439/2768917

function bindIFrameMousemove(iframe){
    iframe.contentWindow.addEventListener('mousemove', function(event) {
        var clRect = iframe.getBoundingClientRect();
        var evt = new CustomEvent('mousemove', {bubbles: true, cancelable: false});

        evt.clientX = event.clientX + clRect.left;
        evt.clientY = event.clientY + clRect.top;

        iframe.dispatchEvent(evt);
    });
};

bindIFrameMousemove(document.getElementById('iFrameId'));

Put pointer-events: none; in the styles for the frame.

I was having this problem myself and found this solution works great and is so simple!