When regenerating, every time without fail, a few odd things will happen. The skin will load fine in third person, and in things like the inventory, but in first person, your skin will revert to how it was in the launcher. With the exception of the arm size, which will still change normally. And the moment you hit "save" to select the next skin to regenerate into, all appearances of the skin only for the client will revert back to the skin they have set in the launcher. (Although I can't remember if it also reverts the arm size as well.) The issue is fixed by just rejoining, but as far as I can tell that also deselects your selected skin, so kind of ruins the point of selecting your next skin ahead of time.

The forge version I use is 1.16.5 36.2.20
and the regeneration mod version I use is 36.0.2

if I need to provide any additional information, like the rest of the mods I'm using and their versions, I will, but I can't see how any of them would affect this stuff since it's not like I'm using something like more player models alongside the regeneration mod, but you never know. I should also note that this discovery was made on a multiplayer server and I don't remember if I tested it in single player yet, but I think it still happens there too. This specific problem never happened to me before so I was confused for a while when it showed up, and I haven't switched forge versions since the last time I used the mod so I don't know why it could be happening.

I do have this problem too

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