title: How to solve "This request has been blocked; the content must be served over HTTPS."?
body: <p>I have an Apex App 20.1 I'm trying to add as an iFrame.</p>
  <p>My app is associated with a domain (example.com) with a valid SSL certificate. My server has a 301 redirection from http to https.</p>
  <p>The app works properly in https at 100%.</p>
  <p>The app loads smoothly in an iFrame. However when submitting a page in my apex app, I'm getting the error :</p>
  <pre><code>Mixed Content: The page at 'https://parentwebsite.com' was loaded over HTTPS, 
  but requested an insecure form action 'http://www.example.com/ords/appschema/r/appalias/pagealias...
  This request has been blocked; the content must be served over HTTPS.
  </code></pre>
  <p>I don't know where this <strong>http</strong> is coming from since my app is entirely loaded in <strong>https</strong> :</p>
  <pre><code>&lt;iframe src=&quot;https://www.example.com/ords/appschema/r/appalias/pagealias...&quot; frameborder=&quot;0&quot;/&gt;
  </code></pre>
  <p>Does anyone know how to solve that please?</p>