monochromer/differential-js-loader.md

## differential-js-loader.md

      
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              differential-js-loader.md
            
          
    This is an alternative to the Modern Script Loading tchnique, that doesn't need to wait for the load event.
Compatibility

This technique has been successfully tested down to IE9.
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <script>
  addEventListener('message', function _(e) {
    removeEventListener('message', _);
    var s = document.head.appendChild(document.createElement('script'));
    s.src = (s.type = e.data) == 'module' ? '/js/modern.js' : '/js/legacy.js';
  });
  </script>
  <script type="module" src="data:text/javascript,postMessage('module','*')"></script>
  <script defer src="data:text/javascript,postMessage('text/javascript','*')"></script>
</head>
</html>
Further Considerations

Please note this technique, or any other out there, does not grant that modern module scripts can also load dynamic import(...) within their code.