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Question for going forward - Is the showcase app likely to expand? As in, how likely is it that over time more and more fields will be added?  If this is the case, then it might be worth considering adding Categories for the Form Field tab control list.

For example Text, Button etc. The question then is whether to list by control type (e.g. 'Text fields')  or functional type (e.g. Text inputs) which would include specific control types ('Text fields'). Vaadin mix these in their documentation, probably a sensible approach". Here you can see the Text input category:

See:

Form fields tab changes

Suggest making a few alterations to the Showcase App: Form fields tab:

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