Error with ember 3.1

Hi, I recently updated ember to version 3.1 and now ember-power-select is not working if I use the selected option.

{{#power-select options=layouts
    selected=selectedLayout
    onchange=(action (mut selectedLayout)) as |layout|}}
  {{layout.name}}
{{/power-select}}

layouts is the result of

this.get('store').findAll('layout')

The error message is

Error: Assertion Failed: You attempted to access the `then` property (of <(unknown mixin):ember757>).
Since Ember 3.1, this is usually fine as you no longer need to use `.get()`
to access computed properties. However, in this case, the object in question
is a special kind of Ember object (a proxy). Therefore, it is still necessary
to use `.get('then')` in this case.

If you encountered this error because of third-party code that you don't control,
there is more information at https://github.com/emberjs/ember.js/issues/16148, and
you can help us improve this error message by telling us more about what happened in
this situation.

it seems to come from this line https://github.com/cibernox/ember-power-select/blob/97621afa0284a2034a52684d80bbf766a981bb43/addon/components/power-select.js#L141

[andrewtimberlake]

Thanks everyone for the help. {async: false} and preloading was the answer

[donaldwasserman]

@cibernox @Titinux - I submitted a PR. As I explain in the #1097, I don’t know if it’s the most elegant, but at least it works.