Possible ownership bug - binding to nested property from class with $state

[midzelis]

Is this a bug or inconsistent behavior?
https://svelte.dev/playground/3057c1db35e745f39d4a73061a9c1e22?version=5.22.6

When passing a class with $state to a component with bindable, if the component binds to a nested property, an ownership failure is logged. However, if the component directly binds to a $state variable then no ownership failure is logged. Playground link shows bug by default. Open console under result in playground to see console logs.

In playground, the rendering/output still worked - however, in my complex real world app, it did not work as expected.

[brunnerh]

This looks like a bug to me. The warning should appear in both cases because the demo property is not actually bound (setting $bindable is just a prerequisite to that).

[benmccann]

I created an issue for this: #15488