As fervor around stablecoins grows from Silicon Valley to Wall Street, one of the most high-profile new crypto projects has drummed up a massive coffer of funds to back its ambitious plans. Tempo, a payments-focused blockchain developed by the fintech giant Stripe and the blockchain venture firm Paradigm, has raised $500 million in fresh funding in a Series A round led by venture giant Greenoaks and Joshua Kushner’s Thrive Capital, according to five people familiar with the matter. The round val...