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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 controls will be added?  If this is the case, then it might be worth considering adding Categories for the Form Field tab control list.

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See: http://demo.vaadin.com/sampler Note that when the information is viewed this way, you get essentially what I would argue for in the Showcase app - a three colum approach with headings that correspond to: 

Control, Image, Description.

Form fields tab changes

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

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