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1. Form fields - Magnolia specific fields. 
2. Vaadin fields - Vaadin fields that can be used with Magnolia.
3. Unsupported fields - Not clear why we specify what Vaadin fields NOT to use. Suggest adding information on what is wrong with each field (i.e. - why it should not be used). That or simply removing this tabThe list of controls is not extensive, implying either that there are many more controls that can be added (in which case the form field tab and Vaadin fields tab are incomplete) or that the list if controls not to use, is incomplete.

All three tabs require changes. To summarize:

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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: http://demo.vaadin.com/sampler

Form fields tab changes

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

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