Clipping effect not working on iOS

[limzykenneth]

I'm trying to build a project with this plane clipping effect from Unity 2018.1.2 to iOS 11.4.1 but I don't get the plane clipping effect at all.

Looking at the Xcode console output are the following warnings which I think is why the clipping effect doesn't work:

WARNING: Shader Unsupported: 'Custom/StandardClippable' - Pass 'FORWARD' has no vertex shader
WARNING: Shader Unsupported: 'Custom/StandardClippable' - Pass 'FORWARD_DELTA' has no vertex shader
WARNING: Shader Unsupported: 'Custom/StandardClippable' - Pass 'FORWARD' has no vertex shader
WARNING: Shader Unsupported: 'Custom/StandardClippable' - Pass 'FORWARD_DELTA' has no vertex shader
WARNING: Shader Unsupported: 'Custom/StandardClippable' - Pass 'DEFERRED' has no vertex shader

Is building to iOS supported at all? If so is there something I should do that I'm missing? Let me know if you need more info. Thanks.

[FracturedShader]

Probably related to #7 since it isn't valid shader code in 2017+ it seems.