The world’s tallest indoor waterfall has started flowing at the new Jewel Changi Airport complex in Singapore. The waterfall feature, which stands 40 metres (131 ft) high, is the central feature of the new S$1.7 billion (US$1.3 billion) mixed-use facility which adds 280 shops and food outlets as well as a hotel and IMAX cinema to the airport’s attractions.   The dome-shaped glass structure was designed by Israeli-Canadian architect Moshe Safdie, who had previously designed Singapore’s iconic…