For drop-down-custom-fields add the option to delete/clear a formally chosen value (is already possible in react)

[n1smithy]

Hello @ all,

I made some drop-down-custom-fields. That's such a nice implementation! But there's a difference between the React- and the Flutter-App:

After chosen one value of the drop-down-menu, this value cannot be cleared again within Flutter. But in React the drop-down-list shows an empty value on top – which is a really valuable option!

Is it possible to put this behavior into Flutter as well?

[hillelcoren]

Thanks for the suggestion!