When using Rubidium to improve rendering performance, catwalk blocks start exhibiting strange culling issues:

I somewhat assume this is a problem in Rubidium (also see my report there), but I'm opening this issue here as well, in case you have some way of working around it.

Upon further inspection, the top culling issue also exists in Fabric in combination with Sodium and Indium, but I couldn't replicate the side culling issue there.
Tested combinations:

• Fabric – FabricAPI 0.58.0+1.18.2, Create-mc1.18.2_v0.4.1+637, Create Deco 1.2.7a-fabric-1.18.2, Sodium 1.18.2-0.4.1+build.15, Indium 1.0.7
• Forge – Forge 40.1.68, Create v0.5.0c, Create Deco 1.2.9-1.18.2, Flywheel 0.6.4, Rubidium 0.5.3a

Happened without Rubidium in Forge's modpack.
It also happens with a lectern instead of a stone.
The handrail must be in contact with the block above.

Fixed for next!