title: Use Javascript to write to file within Chrome and/or Firefox
body: <p>I'm creating a development tool that will be creating CSS based upon an SVG sprite sheet graphic file. This script needs to write out the CSS back to /public/css/main.css. So, no, I'm not interested in a sandboxed file structure (though that is cool stuff). </p>
  
  <p>Keep in mind that this is NOT for production. It is simply a development tool to streamline our workflow (and hopefully benefit the web design/developer community). I have investigated the --allow-file-access chromium switch but still am not sure if it allows write privilege.</p>
  
  <p>So, my question is: How can I write a string to a file using javascript that is running within the browser? Keeping in mind that this is not for production. </p>