Retainer — sign a spend permission

Known limitation — this may not complete for you.

Coinbase's hosted consent screen currently refuses Base Sepolia for newly createdBase Accounts, showing “This chain is not supported.” It is an open upstream issue: base/account-sdk#363. It is not a chain-support decision — the refusal is testnet delegation provisioning for EIP-7702 accounts.

The ERC-4337 path signs and charges normally against the same manager on the same chain; the six confirmed charges on the landing page were made that way. Accounts created before the 7702 provisioning change reportedly still work here.