get value() {
    return this._inputNode?.value || this.__value || '';
  }
We define the value getter/setter below as also defined in LionField (via FormatMixin).
Since FormatMixin is meant for Formgroups/ChoiceGroup it's not applied on Combobox;
Combobox is somewhat of a hybrid between a ChoiceGroup and LionField, therefore we copy over
some of the LionField members to align with its interface.

The view value. Will be delegated to `._inputNode.value`