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I doN't know if it's just me experiencing it, but I see no Try out button in the Oh My Boutique shop. I wanted to see if I need the new items, and try them on, but the option doesn't show up. I can still buy them for points, but I don't want to waste them without trying them on with my doll.
Screenshot:
The furniture items, for me, had a "try it out" button. But like you, no "try it out" button for the clothing.
I have been informed on my profile, that there is not supposed to be a button at all. I totally forgot I just have to move the item in the boutique to my doll. It has been a while since I bought clothes from the shop. >.<
Haha yes the drag and drop makes it pretty easy!
Closing for this is not a bug.