A rupture between Taiwan’s two opposition parties over a mayoral race threatens to spill into November’s elections and erode the fragile trust underpinning their potential 2028 alliance. The main opposition Kuomintang (KMT) and smaller Taiwan People’s Party (TPP) have both registered candidates for mayor of Zhubei, the biggest city in Hsinchu county, after weeks of negotiations failed to produce a joint contender. The KMT has nominated Hsinchu county councillor Wu Hsu-chih, while the TPP’s Chiu...