[1.16.5 Forge] Changing shaders with Optifine causes book model to not rebuild item model

[Kaleidio]

Gives just the pink and black square, but the book can still be opened without graphical issues. it's just the item itself unloading its model. Fixed if the game is restarted regardless of which shader is loaded, which tells me the model is only registering once rather than on resource reload. I have not tested if this is possible with normal resource reload debug keys in a vanilla instance.