Unfortunately, Google has made it impossible to launch screens from the background in Android 10. Therefore, we can no longer show the alarm screen with the big buttons in the usual settings. On Android 10 and newer, the app can only show notifications from the background if the screen is on when the alarm starts. If the screen is locked, we can usually show the full screen alarm.
This is a companion discussion topic for the original entry at https://docs.sleep.urbandroid.org/faqs/fullscreen_alarm_android_q.html