Hello, I'm going through the Schematron book by Erik Siegel and one of his examples improperly passes validation in Oxygen XML while it correctly fails validation using SchXslt. The code for the book is here: [https://github.com/xatapult/schematron-book-code](https://github.com/xatapult/schematron-book-code.git) I open both examples/additional-features/subdocuments-1.sch and data/subdocuments-master.xml from that project in Oxygen and select the tab with the XML file. Then I click the dropdown on the Validation button on the toolbar and click Validate with... and then I select the subdocuments-1.sch file using the dropdown. When I proceed Oxygen says it passes. This is the same approach I have used for all other examples in the book. But I created an explicit validation scenario for this also and it behaves the same way. Note that if you want to test this you should clone the repository because the subdocuments-master.xml file incorporates other files in the repository by reference using XInclude and this is indeed what seems not to be working in Oxygen. By contrast if I run the same validation using the schxslt-cli.jar I get the following, expected result. [invalid] /home/user/task/schematron-book-code/data/subdocuments-master.xml [invalid] /home/user/task/schematron-book-code/data/subdocuments-master.xml failed-assert /Q{}document[1]/Q{}p[1] The class brightred is forbidden (file:/home/user/task/schematron-book-code/data/subdocuments-2.xml)! I am using the latest Oxygen: <oXygen/> XML Editor 25.1, build 2023042509 Thanks, -- Danny MacMillan Sent with [Proton Mail](https://proton.me/) secure email.