Reproduction:
Start the game up, the button will be blank, then lag, then its got a custom theme attached to it.
Observation:
It seems like you put more effort into caching the marketplace on app start then you actually care about putting into the game. (this lag is noticeable each and every app start cycle.)
Suggestion:
Hide this while the app was loading, don't wait to cache the internet on the home screen.
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