Odaily reported that ZKsync posted a notice on the X platform, reminding users that during the protocol upgrade to v26, there is a temporary compatibility issue with the Mailbox contract, which will affect L1 → L2 transactions. L1 → L2 transactions were initially handled by the Mailbox contract, but during the v26 upgrade, due to the bridge and L2 being in different transition stages, the backward compatibility is temporarily not functioning. It may take 1.5-2 weeks to resolve this issue, so users are advised to use "requestL2TransactionDirect requestL2TransactionTwoBridges" on BridgeHub instead of Mailbox, and also to migrate to BridgeHub to avoid the future deprecation of the Mailbox contract.