title: jQuery element position absolute change top on scroll
body: <p>Hi i need position to make <code>fixed background</code> with position absolute and on scroll change top. But my div jump all the time like here in <a href="https://jsfiddle.net/h0xamkv8/" rel="nofollow noreferrer">demo</a></p>
  
  <p>Has someone idea why?</p>