Update to the previous, now-unlisted video, (https://www.youtube.com/watch?v=utQiQPoWTwY) because it turns out there was more to it if you played from the disc so that the game took its time to load.
I cheated to find this but whatever, it’s been 7 years and everyone gave up on trying to find it.
Thanks Nowise10 (https://www.youtube.com/user/Nowise10) for pointing out the text to me after the original video.
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Halo 3 – "Happy Birthday, Lauren!" Load Screen Easter Egg – Birthday Songs
