Metamask: Metamask The method “signTypedData_v4” does not exist / is not available

Bug with Metamask and SignedTypeData in Version 4 (v3)

Since my last update, Metamask has had limitations regarding its support for signed typed data version 4. The “signTypedData_v4” method is indeed not available in the latest protocol standards.

This means that when you try to use signed typed data with Metamask, you will get an error message stating that it does not exist. However, I will provide some workarounds and explanations on how this limitation affects you:

What does “signTypedData_v4” do?

SignedTypedData_v4 is a method used by Ethereum 2.0 to transfer signed typed data between the Ethereum Virtual Machine (EVM) and the signer contract in Metamask.

Why is “signTypedData_v4” not available?

The latest protocol standards for version 4 do not include the “signTypedData_v4” method for signed data. This change may have been made to accommodate new features or improve performance.

Workarounds and workarounds

Since the `signTypedData_v4'' method is no longer supported, you can use one of the following alternatives.

const typedData = new TypedData.SignedTypeDataV2({
type: SignedTypeData_v2,
value : { value : {
// Your signed typed data here
} }
});

• Use a library or module that supports signed typed data: Libraries and modules that provide support for signed typed data are available, such as metamask-unsigned-typedata. These libraries may offer more features and flexibility than Metamask’s built-in support.

• Consider upgrading to Ethereum 2.0: If you plan to use Ethereum 2.0 or related software (such as Metamask), you should note that the latest protocol standards currently support signed typed data.

Conclusion

In summary, due to limitations of the signTypedData_v4 method, it cannot be used with Metamask’s signed typed data version 4. You can still use signed typed data with Metamask by specifying the SignedTypedData_v2 format or by using a library that supports it.

If you are looking for more information on how to work around this limitation, please let me know!