Like so many other Fox News devotees in search of new voids to shout into, Donald Trump loves to tweet. He also, though, happily shares his account with at least one staffer. So how do we know when the most-mad-online president in human history is actually tapping out his own material? Fortunately for us, Trump is a creature of habit, and he's got some tells. In the early days, all it took to figure out whether a tweet came from Trump himself was to peek at the source device.

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