Optimism just approved the upgrade its Superchain needs before interoperability can go live

Optimism approved Upgrade 20, moving its fault-proof system toward the architecture required for future Superchain interoperability.The Ethereum layer-2 network’s governance completed voting on Sept. 16, putting OP Sepolia, Ink Sepolia, Soneium Minato and Unichain Sepolia on course for a targeted Sept. 17 contract upgrade. Mainnet execution is scheduled for Sept. 24 if the new system completes a healthy seven-day testnet soak.The change moves fault proofs from Output Root Dispute Games to Super Root Dispute Games, altering how OP Stack chains challenge incorrect state before withdrawals are finalized back to Ethereum. Optimism describes the upgrade as a prerequisite for interoperability because Super Roots can eventually represent multiple chains at the same timestamp.That interoperability remains a later step. Upgrade 20 keeps each chain’s dispute infrastructure separate, and each new game still contains the Output Root of a single chain. By making the dispute-system transition now, Optimism aims to avoid modifying that security layer again when it activates cross-chain interoperability.The release also bundles changes to Optimism’s contracts manager and SystemConfig, including sa...