Shapes not rendering in builds (investigation megathread)

I'm getting reports of Shapes not rendering when building for certain platforms, and unfortunately I don't know why this keeps happening. There seems to be some cases where GPU instancing doesn't work, even though I've set everything up correctly on my end (as far as I know), and even though the platforms you test on, should support GPU instancing.

This thread will serve as a centralized discussion thread on this issue, as they are likely all related.

It seems like it only happens when GPU instancing is on (correct me if I'm wrong!), which means that somehow GPU instancing is either not supported, or not working even though the platform should support it. This could be due to any number of things, such as, the platform misreporting instancing support, or a plugin disabling instancing silently, or a render pipeline configuration that silently suppresses GPU instancing.

However, GPU instancing is the primary way Shapes makes itself performant, you shouldn't have to disable it.

I would start by testing a few things to investigate further:

1. Do a clean reinstall of Shapes, and see if you still have issues. This is very important to do before reporting any bugs in general. The package manager and Unity in general often struggle to update assets cleanly, so you may have cached files in a broken state, which often leads to weird issues like this. We have multiple reports [1] [2] [3] of clean reinstalls solving this issue
2. Please check for any build or runtime logs for warnings/errors related to Shapes or shaders
3. If you are using immediate mode rendering in Shapes, try disabling immediate mode GPU instancing in the Shapes settings window, and then see if it works. If it works after this, we know that it's related to GPU instancing. If it still doesn't work, then let me know!
4. Unity has a way to check if your current platform actually supports GPU instancing, I would run this on your target platform to double check that it is actually supported.
5. Make sure all shader instancing variants are included in your graphics settings. Unity can't predict which shaders you will use in immediate mode, and so it will sometimes strip them from builds

other than that I'm at as much of a loss as you are - I've implemented instancing support the way one should, it works just fine on many platforms, including iOS and Android for many, so I don't know why it seems to fail in some specific cases. There might be some hidden setting somewhere that disables GPU instancing elsewhere, though that's something I wouldn't know of

Do let me know if you find something out that might help us resolve this!

Reported issues: