From ember-template-lint documentation (https://github.com/ember-template-lint/ember-template-lint/blob/master/docs/rule/no-unbound.md):
```
{{unbound}} is a legacy hold over from the days in which Ember's template engine was less performant. Its use today is vestigial, and it no longer offers performance benefits.
It is also a poor practice to use it for rendering only the initial value of a property that may later change.
```
Co-Authored-By: Jarek Radosz <jradosz@gmail.com>
This new iteration of select-kit focuses on following best principales and disallowing mutations inside select-kit components. A best effort has been made to avoid breaking changes, however if you content was a flat array, eg: ["foo", "bar"] You will need to set valueProperty=null and nameProperty=null on the component.
Also almost every component should have an `onChange` handler now to decide what to do with the updated data. **select-kit will not mutate your data by itself anymore**
