Border child open by default?

[M-Willett]

Is it possible to have a border pane open by default?
Desired behaviour is to create a navigation component in an IDE much like the left sidebar in VS Code (for example: File explorer, Search, Source Control, etc).

To better illustrate, having the highlighted area in the screenshot visible on page load, by default.

[nealus]

just set the selected property in the border to 0:

{ "type": "border", "selected": 0, "location": "left", "children": [ { "type": "tab", "id": "#30b43eab-2da6-4f10-b434-3b0fa3d847c8", "name": "Navigation", "altName": "The Navigation Tab", ...

[M-Willett]

Works! Thank you.