The information on the ADFS configuration page no longer appears to be accurate. The page talks about copying the public key from the `JENKINS_HOME/saml-sp-metadata.xml` file but this file does not appear to contain the public key when the plugin generates the key pair for itself.
For example, our installation created a new key pair after a year. This caused our SAML integration to begin silently failing as the public key was no longer respected by our ADFS. It was quite confusing to figure out how to get the public key from the autogenerated file.