Environment
NetIQ Access Manager 4.2
Situation
After upgrading from Access Manager 4.1 to 4.2, the customised login pages assigned to the IDP server are not being displayed correctly - the branding has changed and some of the links we added are not visible.
Resolution
Make the modifications described in https://www.netiq.com/documentation/access-manager-42/admin/data/b1caoduo.html#bok7icl. There was a change to the IDP JSP framework (REST enabled with simplified branding) in Access Manager 4.2 that requires some small configuration changes to be backward compatible with earlier versions. After making the changes in the above link, everything rendered as before.