Using the XML Schema Changes 2.0.0
The Changes XSD is located here.
Your favorite IDE probably supports validation and/or syntax highlighting for XML files by using XSD schemas. For this to work you need to specify the schema in your changes.xml
file:
<document xmlns="http://maven.apache.org/changes/2.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/changes/2.0.0 https://maven.apache.org/xsd/changes-2.0.0.xsd">
...
</document>