Weird accidental glitch

Portal
1

I just triggered some glitch in testchmb_a_15. It looks like kind of an edge-glitch or save-glitch, yet I’m not sure what is exactly happening.

Here’s a video : https://youtu.be/FEKOO6NvMBE

As you can see, if I jump while edge-glitched, I simply fall through the map, not detecting any collisions (first scene). If I get to reach the top of the platform (second scene), my location changes while I’m just walking around.

Does anyone have an explanation about that glitch? Or has it already been found out?

2

It’s a variant of edge-glitching where you can get save-glitch state without saving.
It’s not well-known so it’s better to add examples, but I have a theory based on invisible walls location that could trigger that kind of effect, but it’s just an opinion and I couldn’t manage to prove it.