Accordingly to recent wildfly master, new attributes were added to elytron, remoting, undertow subsystem and changes to io subsystem from read-write to read-only.

The summary is:

• remoting subsystem, remote-outbound-connection resource: new attribute authentication-context and others marked as deprecated.
• elytron subsystem: new attribute default-authentication-context
• credential-store: new attribute credential-reference
• undertow subsystem, mod-cluster filter: new attribute failover-strategy
• io subsystem: worker attributes are all read-only