title: Adblock. Add css class or remove attribute from element
body: <p>Is it possible to add css rule to an element at some page by adblock? 
  Something like this</p>
  
  <pre><code>#myElement {
      color: white !important;
  }
  </code></pre>
  
  <p>I tried to find a script that updates style of this element on page load but it seems that it is not a best way.  </p>