You must complete Discord authorization before you can access the invite page. A loading bar from 0% to 100% will appear while authorization is prepared.
Press the button below. A loading screen will run (speed depends on your network), then you continue to Discord or the demo path. After success, the invite page unlocks.
Loading 0% to 100% · then Discord OAuth2
Testing without a Client ID? Use the demo path. It still runs the loading screen and unlocks invite the same way.