title: Mixed Content error because of Keycloak default login redirection
body: <p><strong>INFORMATION NEEDED:</strong></p>
  
  <p>I use Keycloak (Docker version) behind a Spring project.</p>
  
  <p>(The client side of this project is React and communication between client and backend is provided by REST services.)</p>
  
  <p>The client side is secured and using "https" scheme.</p>
  
  <p>It is my Spring configuration:</p>
  
  <pre><code>  keycloak:
       auth-server-url: https://sso-ssoha.b9ad.pro-us-east-1.openshiftapps.com/auth
       realm: master
       resource: clientname
       public-client: true
  </code></pre>
  
  <p><strong>THE ROOT OF THE PROBLEM:</strong></p>
  
  <p>When I click a link from client, it calls a Spring service normally.
  But before that, it redirects to default login page of Keycloak with adding this path <strong>sso/login</strong> to the current "https" url but changing scheme to "http".</p>
  
  <p><strong>But, redirecting from https to http create a problem like this:</strong></p>
  
  <pre><code>Mixed Content: The page at 'https://www.helpful.army/contents/Problem' was loaded over HTTPS, but requested an insecure resource 'http://serviceha-helpfularmy.b9ad.pro-us-east-1.openshiftapps.com/sso/login'. This request has been blocked; the content must be served over HTTPS.
  </code></pre>