Intersections and compatibility challenges Combining Seus PTGI, Iris, and Oculus Forge in a single setup (for example, running Minecraft with PTGI shaders on a Fabric + Iris stack while outputting to an Oculus headset) exposes multiple compatibility axes:
This is the classic Flywheel + Shader conflict. Fix: You have not installed the Iris & Oculus Flywheel Compat mod. Go back to Step 3 and install it now.