Outputs page

Scenario - user clicks the checkbox for a property , and a static value is added and saved.

The checkbox remains checked after value saved / Declare Output button is disabled 

If user unchecks the property the Declare Output button is enabled.  If user checks another property , the Declare Output button is disabled.

Although the user doesn't need to check the checkbox for a property to add a static value , many users assume they need to do so for performing any action on a property be it adding a static value or declaring an output