In our Configuration guide, chapter A.22. UNDERTOW SUBSYSTEM ATTRIBUTES, section SERVER ATTRIBUTES, there is attributes table missing for the element:

/subsystem=undertow/server=default-server/host=default-host/location=foo/filter-ref

Note that there is

/subsystem=undertow/server=default-server/host=default-host/filter-ref=foo

already, but this is different element.

Also as there are going to be two 'hash' links pointing to 'filter-ref' now, please make them unique so they both point to correct part of the section (it is similar to the JBEAP-10521).