By Alice PHILIPSON Agence France-Presse HA LONG, Vietnam, May 26, 2023 (AFP) — Squinting in the bright light of a hot summer morning, Vu Thi Thinh perches on the edge of her small wooden boat and plucks a polystyrene block from the calm waters of Vietnam’s Ha Long Bay. It’s not yet 9 am, but a mound of styrofoam buoys, plastic bottles and beer cans sit behind her. They are the most visible sign […]