title: Unable to customize authorisation callback URL for SAML provider after connecting custom domain
body: <p>I'm unable to customize the authorisation callback URL to my custom domain when adding a new SAML provider in Google Cloud Identity platform. I took the following steps:</p>
  <ul>
  <li>I successfully <a href="https://firebase.google.com/docs/hosting/custom-domain" rel="nofollow noreferrer">connected my domain via the firebase console</a>: the status says 'Connected', and the SSL certificate has been provisioned.</li>
  <li>In Identity Platform, I added my custom domain to the authorized domains on the project level.</li>
  <li>I'm trying to add a SAML provider for a tenant.</li>
  </ul>
  <p>I cannot edit the callback url in the cloud console. Also, when adding the provider with a custom url via a client SDK, the provider is created, but again with the default url.</p>
  <p>Any pointers?</p>
  <p>From the documentation:</p>
  <p><a href="https://i.stack.imgur.com/c6pvw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/c6pvw.png" alt="enter image description here" /></a></p>