JSFiddle - React, Tailwind, and code Playground

HTML

<span id="svgWrap">
      <svg id="svg"></svg>
    </span>
    <div id="div"></div>
    <a id="a"></a>
    <div id="nonElements"></div>

JavaScript

function isElement(element) {
      // works on major browsers back to IE7
      return element instanceof Element;  
    }

    // set all elements into HTML
    var svg = document.getElementById('svg');
    var svgWrap = document.getElementById('svgWrap');
    var div = document.getElementById('div');
    var a = document.getElementById('a');
    var nonElements = document.getElementById('nonElements');

    // test on SVG and HTML elements
    if (isElement(svg) && isElement(svgWrap)) svgWrap.innerHTML = "Span and SVG are detected"
    if (isElement(div)) div.innerHTML = "Div is detected";
    if (isElement(a)) a.innerHTML = "A tag is detected";


    // test on a variety of non-HTML elements
    nonElements.innerHTML = ""
    var nonElementArray = [1,true,"text",{},[],0,undefined,false,null];
    nonElementArray.forEach(function(x){
       if (isElement(x)) nonElements.innerHTML = "Oops! Detected a nonElement"
    })

    if (nonElements.innerHTML.length === 0) {
      nonElements.innerHTML = "Successfully returned false for all non-elements."
    }