title: ActiveStorage::InvariableError in Home#index
body: <p>Currently I'm trying to display <code>.HEIC</code> images in Rails 6. I'm using <a href="https://api.rubyonrails.org/classes/ActiveStorage/Variant.html" rel="noreferrer">ActiveStorage ImageMagic</a> to use variant to display <code>jpg</code>. Basically I'm trying to use </p>
  
  <pre><code>mogrify -format jpg myimage.heic
  </code></pre>
  
  <p>In the image to display <code>jpg</code>. </p>
  
  <p>I added <code>Rails.application.config.active_storage.variant_processor</code> into application.rb to be able to use the variant. However it seems to break in the following line:</p>
  
  <pre><code> &lt;%= image_tag post.image.variant(format: 'jpg'), class: "card-home__img" %&gt;
  </code></pre>
  
  <p>Why is not working?</p>