JSFiddle - React, Tailwind, and code Playground

HTML

<div style="border-radius:20px;opacity:0;z-index:-500;" id="test"></div><!--It willl not inflect your design-->

JavaScript

function Is_Compatible(){
    var browser = navigator.appName;
    var Fvar = document.getElementById('test').style.borderRadius;
    if(browser !== 'Microsoft Internet Explorer'){
    return false;
    }
    if(Fvar == undefined){
    //Not IE9+
    return false;
    }else{
    //Is IE9+
    return true;
    }
    }
    if(Is_Compatible() == true){
    alert('Compatible');
    }else{
    alert('uncompatible');
    }