To resolve this, open your Discord app settings (long press the app icon on Android, and select App Info, then go to Set as Default, select Supported Web Addresses, and make sure and *. are both ticked. NOTE: There's a bug that can interrupt the flow between the app authentication from your browser and the Discord app as of writing. Follow the on-screen steps to sign in with your Xbox account and authorize Discord to connect with your Xbox account.

This may prompt you to join the beta program for Discord on Google Play, until it goes public. Scan the QR code using the Discord QR code scan option found in the mobile app's settings.Back on your Xbox, go to the Parties & chats tab of the Xbox Guide menu and select the Try Discord on Xbox banner.In the Xbox app, sign in to your Xbox account.

Download and install the Xbox app on the iOS App Store or the Android Google Play Store.

In the Discord app, sign in to your Discord account.

Download and install the Discord app on a Desktop, the iOS App Store, or the Android Google Play Store.

Discord app download link