When using optifine the railbed of tracks glitch and do no look like they're supposed to, Forming triangle like structures

Steps to reproduce the unwanted behavior:

1. Load game with Optifine mod and Immersive Railroading
2. Open a world up
3. Pull out a Track Blueprint
4. Open properties menu of Track Blueprint
5. Select any block for Railbed option (I choose gravel)
6. Place tracks down
7. Railbed will be glitched and look wrong

The railbed is supposed to be flat and parallel to the tracks placed with it

Screenshots

System Information
OS: Windows 10

System Memory: 48GB

Allocated Memory: 10GB

CPU: Ryzen 2600x

GPU: 2080TI

IR-Version: 1.16.5 forge 1.8.0.1

Forge-Version: 1.16.5 forge 36.2.0

Modlist
alexsmobs-1.11.1.jar
appleskin-forge-mc1.16.x-2.1.0.jar
BetterCaves-Forge-1.16.4-1.1.2.jar
BetterMineshafts-Forge-1.16.4-2.0.4.jar
BetterStrongholds-1.16.4-1.2.jar
Camels-1.16.5-1.0.0.jar
citadel-1.7.2-1.16.5.jar
collective-1.16.5-2.38.jar
ElenaiDodge2-1.16.X-1.1.0.jar
Happy Trails-1.16.5-1.36.0.8.jar
healingcampfire_1.16.5-3.2.jar
ImmersiveEngineering-1.16.5-5.0.0-135.jar
ImmersiveRailroading-1.16.4-forge-1.8.0.1.jar
jei-1.16.4-7.6.1.74.jar
Mantle-1.16.5-1.6.115.jar
mgui-1.16.5-3.2.0.jar
musketmod-1.16.5-forge-1.2.1.jar
MutantBeasts-1.16.4-1.1.3.jar
nohostilesaroundcampfire_1.16.5-3.3.jar
OptiFine_1.16.5_HD_U_G8_MOD.jar
presencefootsteps-r29-1.16.4.jar
randomloot-1.16.5-2.3.9.jar
rare-ice-0.2.2.jar
rpgbackpacks-1.16.5-1.1.5.jar
sit-1.16.5-v1.3.1.jar
smallships-1.16.5-1.9.1.jar
SoundFilters-0.14_for_1.16.2.jar
Construct-1.16.5-3.1.0.231.jar
TerraForged-1.16.5-0.2.13.jar
tetra-1.16.5-3.14.1.jar
TrackAPI-1.16.4-forge-1.2.1.jar
Universal ModCore-1.16.4-forge-1.0.1.jar
worldedit-mod-7.2.5-dist.jar
Xaeros_Minimap_21.14.1_Forge_1.16.5.jar
XaerosWorldMap_1.16.0_Forge_1.16.5.jar
YungsApi-1.16.4-Forge-11.jar

latest.log
2021-07-30-1.log.gz

Additional context
As soon as I removed Optifine from the modpack the Railbed glitch went away so I am certain having all these mods was not the problem.
I need optifine with this modpack because otherwise the game stutters quite a lot and my fps drops. So fixing this problem is the only way.

This has been fixed in the test build which will be released in a few days. You can download it from the pinned link in #test-builds in discord. You will need both IR and UMC for 1.16.5

This has been fixed in the test build which will be released in a few days. You can download it from the pinned link in #test-builds in discord. You will need both IR and UMC for 1.16.5

Will Do, Thanks!