Jito Disables Solana Mempool Feature After Front-Running Attacks

• Jito developer disables "mempool" function in its Solana client after spate of sandwich attacks • Mempools hold unconfirmed transactions before they are added to the blockchain • Jito had enabled front-running attacks by permitting transaction reordering in mempool • Decision a reversal after Jito recently allowed front-running, deeming restrictions unenforceable • Over half of Solana validators used Jito's alternative client before decision to remove feature