What are the colonies up to @stripe .. this is not (yet) the flag of Germany. #bugreportpic.twitter.com/zH2CxrFOOE
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Moin Erik, it means that you're currently viewing the Australian site, but based on your location it recommends for you to switch to Germany. Once you click "Wechseln" you should see the beautiful German flag
But I agree that it's not really clear, will let the team know 
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