If you throw an ender pearl into the end fountain after defeating the ender dragon, you get teleported to the overworld by the ender pearl, thus not triggering the credits.

How to reproduce:

1. Open a new world, or a world where you haven't seen the credits yet.
2. Go to the end and defeat the ender dragon
3. Throw an ender pearl into the portal. Make sure to use a shallow angle to ensure the pearl gets teleported before hitting any blocks.
   
4. No credits are shown

Expected result:

The credits should be reliably shown after defeating the ender dragon independent of how the player travels through the end portal.