Anant,
The blank white screen probably means that the response from the federation module is not being recognized as a login trigger by the Reverse Proxy. You can confirm this by looking at a browser trace of the "white page" response and see if there are eai-.... headers in there.
If you see these headers then it means you need to run the Federation configuration wizard for the OIDC federation definition. I know you've done this before for SAML - just repeat the steps but pick the OIDC federation instead. That should resolve the issue.
Jon.
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Jon Harry
Consulting IT Security Specialist
IBM
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