How to add TwoPaneSplitView?

Hi,
Good day to you.

How can I split my custom Editor Window using the UnityEngine.UIElement.TwoPaneSplitView? Should I add it in the UXML or in the C# script? If I add it in my UXML I can only see it in the UIBuilder but not in my actual custom window. If I add it into my C# script it shows in my custom editor window but not in the UIBuilder, I can’t edit or integrate it with my other VisualElement.

Solved. Added using UXML works fine. Just need to change min-height and min-width of it from auto to pixels.