The European Union is set to launch an investigation into Temu over concerns it is failing to curb the sale of illegal products online, in a probe that could lead to hefty fines for the e-commerce service.The European Commission will open formal proceedings against the platform — run by Chinese-owned PDD Holdings Inc. — to probe whether it is in breach of rules against illicit online activities, according to people familiar with the matter, who asked not to be identified discussing confidential ...