LONDON/SINGAPORE—Cryptocurrency Ethereum broke $4,000 for the first time on Monday, climbing to a new peak for a third day in a row on bets it may find new uses, although some analysts said it was overvalued at current levels. Ethereum, the second-largest coin by market capitalization, jumped more than 6 percent to just below $4,175, and was last up around 2 percent. It has soared this year, fueled by expectations of wider use, based in part on its role in decentralized finance—DeFi—platforms that facilitate crypto-denominated lending outside traditional banking. An upcoming technical change to its software seen as reducing its supply has also provided a boost, while new institutional investors in the crypto sector have warmed to it amid a tepid quarter so far for Bitcoin. “(Crypto has) got a lot more institutional involvement than people who haven’t followed the market believe,” said Chris Weston, head of research at brokerage …