Godot 4: Another video glitch shader (tutorial)

Hi everyone! Let's add a simple effect simulating a TV signal disturbance to our collection. It actually resembles typical artifacts when playing recordings from a low-quality VHS tape, but it's up to each programmer to find a suitable use for it. And because it's a very simple algorithm with just a few lines of code, this video will be relatively short as well. So let's create it.