[bug] MetaMask mobile wallet connects successfully with unsupported chain (displays 'Chain 1")

[meri-maki]

Link to minimal reproducible example

https://github.com/meri-maki/useSwitchNetwork

Summary

I have a project that should only work with certain chains [polygon, arbitrum, bsc, sepolia] When I connect my mobile Matamask wallet (either with WalletConnect or from list of wallets on mobile) with Etherium chain selected, it connects with no errors

Web3Modal Network button displays it as 'Chain 1'

This is very confusing behavior... How is it possible for Metamask to even connect to the unsupported chain?

This can be replicated on local host with min rep example

List of related npm package versions

    "@web3modal/wagmi": "^3.1.0",
    "viem": "^1.16.2",
    "wagmi": "^1.4.3"

[glitch-txs]

MetaMask will connect to the chain you have opened in the mobile wallet app not the website

[meri-maki]

@glitch-txs is there any way around it...? Why it's displayed as "Chain 1"?

[meri-maki]

The one fix I found is to declare defaultChain, but we would like to avoid this behavior

[meri-maki]

@glitch-txs do you think it's reasonable to mention this issue on wagmi? or is this issue exclusive to mm mobile wallet, and there is nothing we can do?

[glitch-txs]

you can open an issue in MetaMask mobile repository, it's on their end only.