I'm developing a website that uses `personal_sign` to authenticate users. I send the "address" and "signature" to my server to verify the user owns the address. I'm currently adding WalletConnect support, and ran into an issue with Gnosis Safe. When signing with Gnosis Safe, the value of `signature` is just "0x" instead of the full signature:

```
const signature = await connector.signPersonalMessage([
  convertUtf8ToHex(message),
  address,
]);

```

Is `personal_sign` supported by Gnosis Safe? This technique works with WalletConnect when connecting with Ledger Live or the Metamask mobile app. Is there an alternative way to verify a user owns an address?

Thank you.