title: How to force hardcoded value of JavaScript screen.width?
body: <p>I am using a web application that wants to be used full screen.  My screen is so wide that the application is nearly unusable full screen.  More to the point, the application does deserve that much real estate.  I am willing to give it ~1/3 of the width and I do useful work in the other 2/3.</p>
  
  <p>I am convinced that this application uses JavaScript's screen.width to set the size of it's GUI bits.  So, I am looking for a way to have my tool (my browser, for example FireFox) return a value of my choosing.  Ideally, the same as window.width().</p>
  
  <p>Maybe I would enable such a feature for specific URLs.  More likely, I would apply this to everything.</p>
  
  <p>Can this be done as an "extension"?  If I need to, I can get the code to FireFox and put the feature I want in there.</p>
  
  <p>What about Chrome?</p>