v5.9.0 WebGL Android Mobile Browser - Connect Feature - window.ethereum is undefined causing Metamask Deeplink Not Working

[quurkyhongyu]

The window.ethereum is undefined on mobile browser, therefore before the Connect try to switch ethereum chain, it failed to get the instance and return false

The code below is from MetaMaskWallet.cs & WebGLMetaMask.jslib, I believe the jslib function below to check the wallet was existed or not in browser. But I think it is not for case like webgl mobile browser;

// MetaMaskWallet.cs
if (metaMaskInstance.IsMetaMaskAvailable())
{
    // switch to ethereum network...
}
else
{
    throw new Exception("MetaMask is not available.");
}

// WebGLMetaMask.cs
public async Task<T> RequestAsync<T>(RpcRequest rpcRequest)
{
    var rpcRequestMessage = JsonConvert.SerializeObject(rpcRequest);
    _rpcResponseCompletionSource = new TaskCompletionSource<string>();
    
#if UNITY_WEBGL && !UNITY_EDITOR
    Request(rpcRequestMessage, gameObject.name, nameof(OnRequestCallback), nameof(OnRequestFallback));
#endif

    var response = await _rpcResponseCompletionSource.Task;
    var rpcResponseRaw = JsonConvert.DeserializeObject<RpcResponse<T>>(response);
    if (rpcResponseRaw.Error != null)
    {
        throw new Exception(rpcResponseRaw.Error.Message);
    }
    return rpcResponseRaw.Result;
}

// WebGLMetaMask.jslib
IsMetamaskAvailable: function () {
  return window.ethereum ? true : false;
}

[warengonzaga]

Hello @quurkyhongyu, we received your ticket, and I'm tagging @0xFirekeeper for an extra eye and explanation about this. However, we recommend using native builds for mobile instead of using WebGL for your mobile app, as this is a known issue.