Group filtering option is not available for applications configured with OIDC or Oauth with Azure AD. This option is available only for applications configured with SAML protocol.
This is documented in article https://learn.microsoft.com/en-us/azure/active-directory/hybrid/how-to-connect-fed-group-claims#important-caveats-for-this-functionality.
You can search for words "Group filtering applies to tokens emitted for apps where group claims and filtering was configured in the Enterprise apps blade in the portal."
The group base filtering option is available for applications in enterprise apps blade. Once you open application in enterprise apps, you have to click on "single sign on " blade.
And configuration under "single sign on" blade is done only for apps which are configured to use SAML protocol.
For now, this option is not available for applications configured to use OIDC or Oauth.
You can submit your feedback in Azure feedback portal https://feedback.azure.com/d365community/forum/22920db1-ad25-ec11-b6e6-000d3a4f0789
Let me know if you have any further questions.
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