JSFiddle - React, Tailwind, and code Playground

HTML

<div id="divtoshow" style="display:none">test</div>
<br><br>
<span onmouseover="ShowHoverDIV('divtoshow')">Mouse over this</span>

JavaScript

function ShowHoverDiv(divid){

    function(e){
        var left  = clientX  + "px";
        var top  = clientY  + "px";
        $("#"+divid).toggle(150).css("top",top).css("left",left).css("position","fixed");
        return false;
    }


}