title: Wordpress: Featured images all showing with 1px width and 1px height
body: <p>I'm not sure what exactly has caused this, but either after upgrading to the latest WP version or using WP.SmushIt plugin, <a href="http://ztwealth.com/" rel="nofollow">all my featured/thumbnail images</a> are displaying with 1px width, and 1px height. </p>
  
  <p>The regular images used inside the pages/content are fine, only those that I'm calling using <code>get_the_post_thumbnail($post_id, 'carousel-thumb');</code> are broken. </p>
  
  <p><code>carousel-thumb</code> is just a custom size I've defined in my functions.php like <code>add_image_size( 'carousel-thumb', 220, 220, true ); //(cropped)</code>  </p>
  
  <p>Any help is appreciated. </p>