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Have you put a root view in yet?

There needs to be one background root view that everything else is placed in.

(Send us a screenshot if your problem isn't that so we can help you better.)
 
I don't think you are supposed to prevent it. It is just a default behavior which causes new resizable objects to snap to the bounds of the view. Once you place it in, you can grab the corners or sides and resize it though.
 
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