For a while we have been talking about the upcoming removal of legacy security after WildFly Elytron was introduced in WildFly 11.

The time has now come to commence the removals, the first area being handled is the removal of the PicketBox vault integration.

More information is available in the following analysis proposal:
    https://github.com/wildfly/wildfly-proposals/pull/405

Regards,
Darran Lofthouse.