title: Can anyone suggest solution for page scrolling with arrow-keys in firefox, when modal is open?
body: <p>I have created a webpage, that opens a absolute modal-like-dialog on button click. As the basic, i append 
  <code>body { overflow:hidden; }</code> 
  using jQuery to prevent background page scroll. this works with everything and prevents scroll with mouse. (FF and Chrome - both)</p>
  
  <p>Issue comes with FF when I press arrow keys on keyboard. Page scrolls. (tho it doesn't show scrollbars.) Does anyone face the same problem or Is this a known bug? I would like if anyone can suggest CSS only solution.</p>