A €3 customs duty has dramatically reshaped Europe's online shopping landscape in just one month.Since July 1, the European Union has imposed a flat €3 customs fee on parcels valued under €150—a move that has already slashed imports from Chinese platforms by 30% to 40%, according to French customs data cited by the economy ministry.The measure targets the flood of low-cost goods that have long poured into European letterboxes from Shein, Temu, and AliExpress. What Brussels once allowed duty-free...