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- United Airlines flight attendants picketed outside LaGuardia, Austin, Guam, and London airports.
- They've been negotiating for a new contract for over two years, their union said.
- CEO Scott Kirby's pay almost doubled to $18.5 million last year.
United Airlines flight attendants were picketing outside 17 airports around the world on Thursday in a protest about pay, the Association of Flight Attendants-CWA said.