Bug with STP and PAC3 that warps player models

[RubisDrake]

Hey everyone, I got a strange bug here that warps player models.
Not sure if the problem is PAC3, Simple Third Person, or Gmod act commands itself, but here it is:

1. Install and enable PAC3 and Simple Third Person addon from the workshop (very important, bug won't show without STP enabled.)
2. Start a map and open PAC3, make sure third person view is already enabled. It has to be on before the map loads, essentially.
3. Insert a new Custom Animation into the default "my outfits" group.
4. Hide interface (Ctrl+E) and use act dance or any other act command.
5. Move the mouse cursor around
6. Voila, character model gets warped!

Did nobody ever know about this? Custom Animation seems like a fairly buggy thing in general.
I'm not sure if this is STP or PAC3's fault, but I thought I'd share this here just in case.