title: Embedding SWF file in HTML5 - How to add alternative content?
body: <p>I'd like to embed an SWF file in HTML5. It works fine with this code:</p>
  
  <p><code>&lt;embed src="main.swf" width="550" height="400" /&gt;</code></p>
  
  <p>But how could I show alternative content (an animated GIF image, or a static JPEG or PNG) just in cases which swf file is not supported (and still validating in w3! ;) )</p>
  
  <p>Thank you!</p>