GSit's /sit command causes player to float in 1.20.1 and under

[Kichura]

'/viaversion dump' Output

https://dump.viaversion.com/4b655560c83e2676859c31806bd13144783756a0d9f5331894e152ee8c69ff5e

Console Error

(No console errors have been discovered in console)

Bug Description

When playing on 1.20.1 or older on a 1.21[.1] paper server, using GSit's /sit command causes the player to float mid-air instead of properly sitting on the block itself.

1.20.1 POV:

1.20.2 POV:

Steps to Reproduce

1. Install GSit 1.10.0 to the server,
2. Get both ViaBackwards and ViaVersion from the jenkins website,
3. Make a new paper 1.21[.1] server with no config changes applied,
4. Join the server with vanilla 1.20.1 client or older and run /sit,
5. Player should float instead of properly sitting.

Expected Behavior

The player is properly sitting on the block like in 1.20.2 and above.

Additional Server Info

1. This server does not make use of any proxies,
2. Fedora Linux 40 with Paper 1.21.1, (Build 128)
3. GSit 1.10.0, ViaVersion 5.1.1-SNAPSHOT and ViaBackwards 5.1.0-SNAPSHOT.

Checklist

• [X] Via plugins are only running on EITHER the backend servers (e.g. Paper) OR the proxy (e.g. Velocity), not on both.
• [X] I have included a ViaVersion dump.
• [X] If applicable, I have included a paste (not a screenshot) of the error.
• [X] I have tried a build from https://ci.viaversion.com/ and the issue still persists.

[Barvalg]