Quantum Chain (Qtum) added the offline staking function in the new version of the full-node Qtum Core Wallet 0.19.1, which involves the upgrade of the consensus protocol, so the Qtum mainnet will be hard-forked at a block height of 680,000. The estimated time is August 28 Beijing time. The launch of offline staking will enable Qtum users to maintain their online full nodes independently and delegate their own Qtum to super nodes to perform Stake and obtain block rewards. And users who want to become a super node only need to perform simple configuration and maintain the full node online to provide services. The super node and the entrusted user will negotiate to determine a fee ratio, and extract the block reward obtained from the entrustment to pay to the super node.