I created a new category in the XML configuration view of the server
called Server and added a new XPath like this:

Name: jmx invoker

XPath Pattern: /server/mbean/xmbean/operation/descriptors/interceptors/interceptor

It worked fine first time around but now, although I can see the XPath, I can't see the
matched XML files. Same happens in the "Ports" category.

I'll attach screenshot.