Since Java 1.7 both the XML APIs and the default implementation for it are part of the JDK. Since then neither the xml-apis nor the Xerces artifacts should be used anymore.

The goal is to get rid of all Xerces dependencies. In most places we can just remove the dependency because both Xerces and Jaxp use and provide the same API. Some places (like in main) are a little bit more tricky because the Xerces classes are used explicitly which require some small code changes (see MAGNOLIA-5983).
Some 3rd party tools we use like NekoHTML in diff, use internal classes of Xerces. This means we have to remove the use of those libraries as well. For this we had to create our own fork of daisyDiff.