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Now, when someone @mention you on Instagram and shares it to Twitter, Instagram will automatically translate your username in the tweet it sends to match your Twitter handle. It will do this so long as your Instagram and Twitter accounts are linked.
For example, if I mention my colleague Chris Taylor (@futurechris on Instagram and @futureboy on Twitter) in a photo caption and share it to Twitter, it will appear as @futurechris on Instagram and @futureboy on Twitter.
It's a much-welcome update from the mobile photo-sharing app, which was acquired by Facebook earlier this year.