So, I first thought it would be Mo'Bends that causes this issue, and as such I removed the mod from my client, but it still doesn't work. Whenever I shrink myself or change size, my camera/eye height changes and I can move between blocks, so my hitbox is changed, but my character model stays the same size as it always does, and I am not sure how I can fix this. Please advise.

Pics (Shrink 2 was applied to myself):

Can I ask for a list of mods?

Oh of course, my mistake:

If you need anything else just tell me :D

Okay, here's my ideas: Cyberware, Mob Dismemberment, or Obfuscate. Those all mess with player models, so it's possible that one of them replaces the player model with a custom one.

Hmm very likely (I hope not) Cyberware, will try without.

Currently going through them myself as well. So far have figured out it's not Mob Dismemberment

For me neither, also not Cyberware, left is Obfuscate (which is a part of MrCrayFish Vehicle Mod and such)

Interesting, it's none of those 3...

Yep, I also came to that conclusion now. Wtf is causing this?

I have one other idea that I'm trying now. Well, one other mod that it might be. If that's not it, then I do have one idea that will have made all of this pointless had I just tested it before.

I'm stumped. It's not even Mo' Bends. I thought maybe after you removed it, it didn't update the player render while the effect was still active, and needed to be reapplied, but Mo' Bends works fine.

Yup, also tried that but again, no result.

I will have to remove the mods in blocks, see which one may cause it, it will take time.

We'll try and help. Someone suggested a few mods, which I'm testing now. Someone else said Optifine might be it, but I'm doubtful. If you want to try Optifine, go ahead.

Well I can hardly imagine why Optifine would do something like that, it works well with other mods that modify character model behavior as far as I know. But sure, I can try.

WTF, well, of course it had to be Optifine because why the fuck not.

Wait, it was Optifine?

For whatever reason yeah it was, I will add back all the other mods and test without Optifine.

Well... that's unfortunate. Thanks, Optifine

Well can you not find a fix for it? Usually everyone is able to work around it somehow.

I'll report it as a bug to Optifine. It's 100% a thing to do with ArtemisLib, so we'll have to work with that.

I see, hope you can get it fixed soon :D

Ok so, I readded ALL other mods that were suspected, they all work perfectly fine with the resizing mod, so it is ONLY Optifine (not surprised).

I'm still kinda surprised about that. I know Optifine can be buggy with mods that do things performance wise, but I didn't think it did anything to entity renders.