JSFiddle - React, Tailwind, and code Playground

HTML

mouse<b>move</b> here...
<div id="whichkey"></div>
<p id="log"></p>

CSS

#whichkey {
    height: 50vh;
    background: gold;
}

JavaScript

var pressedLog = $('#log');

$('#whichkey').bind('mousemove', function(e) {
    pressedLog.html('Pressed:<ul>' + 
    				'<li>e.buttons: ' + e.buttons + 
                    '</li><li>e.which: '  + e.which + 
                   '</li></ul>');
    
    //Fade out when the mouse stops moving:
    //http://stackoverflow.com/a/1421338/1869660
    pressedLog.stop(true).css({opacity:'1'}).show();
    pressedLog.fadeOut();
});

/* Note:
	e.which is always 1 in IE/Firefox:
    https://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/which#Browser_compatibility
    https://bugzilla.mozilla.org/show_bug.cgi?id=1048294
*/