How to make The Best First Person Camera in Unity

I've been playing around with different camera configurations in Unity to achieve a non-jittery camera and I think I might've come across the best solution.

Timestamps:
0:00 - Introduction
0:42 - Chapter 1: Understanding the problem
1:45 - Chapter 2: FixedUpdate vs Update
4:56 - Chapter 3: The solution
5:17 - Chapter 4: The solution part 2
6:18 - Chapter 4: The solution part 3

#unity

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Daystar - Lemon Cake
A Hat in Time - Train Rush [Remix] by Qumu
Cinematic - Aylex
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Lamp - Kyatto
Once - RYU ITO MUSIC