Hello,
when using the DarkMetro theme, the node lines are not drawn correctly. See attached image.
Using v16.1
Hello Markus,
Thank you for contacting Infragistics. I was not able to reproduce the behavior. I've attached a sample and I'd like you to please update and send it back to me and I will investigate this further. Please see my attachment and let me know if you have any questions.
I modified your example with a 3rd node level. Here you can see it. Just open the first node with its sub nodes.