It’s slightly hard to describe this, but I figured out how to make a small clip of the issue…
Basically what happens is when I try to reorder the playlist by clicking and dragging a video in the playlist to elsewhere, a different video entirely gets moved. Doesn’t seem to have a correlation between videos.
I used Microsoft Edge and the issue persists. I’m using Chrome to watch on Watch2Gether, with my version being the latest (86.0.4240.75 ; 64-Bit).
I remember this being a problem I had some years back but it randomly fixed itself.