Expected behavior Collapse and expand to work as expected on treeview

Actual behavior when you collapse a depth-1 item, and then you expand it again, the depth-2, depth-3 icons points to bottom but the content inside remains collapsed. It should expand the content inside or change the icon to point to the right. Then when you click on the icon, it expand the content but don't spin, and if you click again starts to work as expected.

Resources (screenshots, code snippets etc.) I get this behaviour in your own example on the web.