Immediate mode polylines not rendering in VR

I have a project that uses immediate mode polylines in a VR game. I am upgrading my project from Unity 2021.3.45 + Shapes 4.3.1 to Unity 6000.4.2 + Shapes 4.6.0. It still works almost perfectly, except polylines do not render in build on headset (Quest 3)

The immediate mode polylines still render correctly in editor as well as in WebGPU builds. I am able to place regular polylines in scene and see those in headset, so the problem is limited to immediate mode. No errors or anything at runtime. I've been messing around with settings and cannot for the life of me figure out why this is happening. Any ideas?