Replacing the default ingress certificate in OpenShift 4.x causes x509 error for webconsole, logins, monitoring and oauth applications

Issue

• After following the instructions for replacing the default ingress certificate, the web console and monitoring components becomes inaccessible.

• The certificate applied to the ingress router was generated by a private/custom certificate authority;

• When I go to login or pod logs, I get an error:

  error: x509: certificate signed by unknown authority
  

• Using any OpenShift component that uses the oauth-proxy/oauth-server does not work, getting 500 Internal Server Error;

• Unable to open Grafana/Alertmanager/Prometheus GUI as it throws 500 Internal Server Error on the screen.