title: Robot Framework CSS attribute selector
body: <p>The Selenium documentation for Get Element Attribute gives an example of:</p>
  
  <pre><code>${id}=  Get Element Attribute   css:h1  id
  </code></pre>
  
  <p>However, this selector doesn't function for me:</p>
  
  <pre><code>${VISIBILITY}=    Get Element Attribute    css:visibility    mySidebar
  </code></pre>
  
  <p>where the HTML is:</p>
  
  <pre><code>&lt;div id="mySidebar"&gt;
  </code></pre>
  
  <p>and the attribute visibility is:</p>
  
  <pre><code>Style Attribute {
      z-index: 104;
      visibility: visible;
  </code></pre>
  
  <p>What is a functioning selector for this?</p>