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Okay enough of surprises.

This is how you do it.

http://m.youtube.com/watch?v=YBg8-tQzNu0
 
Has no one noticed the obvious? It is obviously not the GM and just a hack because when zoomed out the folder doesn't show that it contains an inner folder - that is just terrible UX. What if you have a folder of folders? The icon would be completely blank.

Obviously he just enabled it somehow in beta 6.
 
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