title: knockout.js Uncaught TypeError: Unable to process binding
body: <p>I am using Porto v2.2.0 – Ultimate Responsive Magento Theme and showing error like </p>
  
  <pre><code>knockout.js:3012 Uncaught TypeError: Unable to process binding "css: function (){return { empty:cart().summary_count == 0} }"
  Message: cart is not a function
  </code></pre>