Custom element properties and binding

I’ve created two custom elements, a list and list item. The list element takes one bindable property called ‘lines’. Inside the template is a . List item elements are used inside list. The template uses the parent ‘lines’ attribute to determine the markup it should render.

Up until a few days ago this worked fine, but now i’m noticing that list-item is adding it’s own property called ‘lines’ which is set to undefined.

Has something changed in binding to make this occur?

can you create a to show your vms and markup?