Therefore, the question arises whether you are using Flash Builder 4 or Flash Builder 4.5
I tested this in Flash Builder 4.5 and it works without any problems. And yes, I really had to check this because I did not use the development mode, because well .. forever: P
You should use Flash Builder 4.5 if you really need to use a design view.
The update takes place at a very reasonable price.
Greetings
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