Alpenglow on Solana can finalize a block in one round if 80% of stake votes for it, or in two rounds requiring 60% of stake per round

From the articleSolana Activates Alpenglow on Mainnet, Swapping Out TowerBFT for a Faster Consensus Engine - UnchainedAlso in Solana Alpenglow Goes Live in 'Most Ambitious' Upgrade Since Ethereum's Merge - Decrypt