According to ChainCatcher, Polygon Labs announced that the Miden Alpha testnet v3 is now online.

It is reported that Polygon Miden is a zkVM rollups that is still in the testnet stage, enabling users to create and execute their own zero-knowledge proofs. Currently, Polygon Miden Testnet v3 supports standardized user operations and smart contracts. Future updates will enable developers to execute any logic on or off the chain like other general blockchains.