Contract keys not supported in Daml Studio?

I am learning Daml in Daml studio (VS Code) and getting an error message when I hover over a template that uses contract keys:

Failure to process Daml program, this feature is not currently supported.
Contract keys.

template CustomerTokenBalance
  with
    customer : Party
    tokenId : Text
    balance : Decimal
  where
    signatory customer
    key (customer, tokenId) : (Party, Text)
    maintainer key._1

Should I not use contract keys or is there a fix?

I switched to sdk-version: 2.10.0 and keys seem to be supported.

Switching to 2.10.0 resolved this because Contract Keys is not supported in 3.x. This allows 3.x to support multiple domains, which is important for supporting the long-term development of the Canton Network. Contract Keys will remain supported by the LTS releases of 2.x.

It is possible that something resembling keys may be included in a future version of 3.x; however, the uniqueness guarantees provided by the feature in 2.x are fundamentally incompatible with the improved distributed ledger features that underpin Canton in 3.x.