CodePen

HTML

            
              <p>Bug: <span id="bug"></span></p>
<p>Hack: <span id="hack"></span></p>
<p>Hidden Hack: <span id="hidden"></span></p>
            
          
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↑ Insert the most common viewport meta tag

CSS

            
              
            
          
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JS

            
              var bug = document.getElementById('bug');
var hack = document.getElementById('hack');
var hidden = document.getElementById('hidden');

var fragBug = document.createElement('div');
var fragHack = document.createElement('div');
var fragHidden = document.createElement('div');

//All empty elements causes bug
fragBug.innerHTML = '<span></span><script>alert("test")<\/script>';

//Adding any text hides the bug
fragHack.innerHTML = '<span>any text</span><script>alert("test")<\/script>';

//A way to use the hack without effecting flow.
fragHidden.innerHTML = '<i style="display:none;">&nbsp;</i><script>alert("test")<\/script>';

bug.innerText = fragBug.innerHTML;
hack.innerText = fragHack.innerHTML;
hidden.innerText = fragHidden.innerHTML;
            
          
!
Must be a valid URL.
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via JS Hint
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