When I open `demos/form-control/scope-builder.php` demo and change the model to `Atk4\Ui\Demos\File` which has `boolean` field and then: click/add that boolean field:  and click `Save` (on the ScopeBuilder demo) I get: 
When I open
demos/form-control/scope-builder.phpdemo and change the model toAtk4\Ui\Demos\Filewhich hasbooleanfield and then:click/add that boolean field:
and click
Save(on the ScopeBuilder demo) I get: