I upgraded EBS Version from 12.1.3 to 12.2.9. After upgraded, i planned to setup the Java webstart for EBS 12.2.9 version. As such, i review the document (Doc ID 2188898.1), this document clearly explained about how to setup the java webstart on EBS.
There was many patches noted to apply on EBS version for java webstart. But my case, I have already upgraded to latest version. so all the patches are included whichever required.
Section : 4.2.2 Oracle Forms 10g Technology Patch for Oracle E-Business Suite Release 12.2
the document noted to apply the patch Patch 25441839 but Patch 26825525 already applied during upgrade activity. so no need to apply the patch 25441839 (Doc ID 2554599.1).
you need to follow further steps for Java webstart setup.