Took some tinkering, but I got this to work in 2026 using the pattern originally described in the above answer from @chaitanyapotti.
- The goal was to get wildcard subdomains working with embedded wallets in Web3Auth (MetaMask SDK). See https://builder.metamask.io/t/embedded-wallet-web3auth-login-does-not-work-with-wildcard-subdomains-whitelisted-even-though-it-says-they-should-work-in-the-docs/3388/7
Our application deploys a unique preview hostname for each pull request, for example: