Not able to sign wasm messages with Keplr connected to Ledger

I have been looking into this issue for a few days as I have experienced this issue on my own project. Ledger does not support the protobuf message type and needs to fall back on the amino encoding.

This issue can be repeated on the example dApps running on https://dapps.juno.giansalex.dev/wallet/.

Is there a way to force CosmJS and Keplr to use the amino message type? I have tried window.getOfflineSignerOnlyAmino(chainId: string) as recommended in https://docs.keplr.app/api/cosmjs.html, but that seems to break the Keplr integration.

Would love to know if there is an existing workaround for this issue. Going to keep investigating and see if I can identify a fix.

[giansalex]

@ben2x4 you need to use getOfflineSignerAuto

Also, window.getOfflineSignerAuto(chainId: string): Promise<OfflineSigner | OfflineDirectSigner> or window.getOfflineSignerAuto(chainId: string): Promise<OfflineSigner | OfflineDirectSigner> API is supported. Please note that the value returned is async. This API automatically returns a signer that only supports Amino if the account is a Ledger-based account, and returns a signer that is compatible for both Amino and Protobuf if the account is a mnemonic/private key-based account.

[assafmo]

I can confirm that @giansalex’s comment solved this for me too! Ledger signing started working after I switched getOfflineSigner for getOfflineSignerAuto (code reference). 🎉