Using instancing on HDR color causes crash?

For some weird reason when I try to define the following color:

Code (CSharp):

1. [HDR] _EmissionColor("Emission Color", Color) = (0, 0, 0)

In the instancing buffer:

Code (CSharp):

1. UNITY_INSTANCING_BUFFER_START(Props)
2.     UNITY_DEFINE_INSTANCED_PROP(half, _AlphaCutout)
3.     UNITY_DEFINE_INSTANCED_PROP(half, _NormalCutout)
4.     UNITY_DEFINE_INSTANCED_PROP(half, _NormalAppliance)
5.     UNITY_DEFINE_INSTANCED_PROP(half4, _Color)
6.     //UNITY_DEFINE_INSTANCED_PROP(half4, _EmissionColor)
7. UNITY_INSTANCING_BUFFER_END(Props)

Once I uncomment that half4 _EmissionColor line my Unity Editor simply crashes. What am I doing wrong?

I've also tried float4 with same result.

This is on Unity v. 2018.2.3f1

 

Using second "Property Block" seems to be working just fine like so:

Code (CSharp):

1. UNITY_INSTANCING_BUFFER_START(Props)
2.     UNITY_DEFINE_INSTANCED_PROP(half, _AlphaCutout)
3.     UNITY_DEFINE_INSTANCED_PROP(half, _NormalCutout)
4.     UNITY_DEFINE_INSTANCED_PROP(half, _NormalAppliance)
5.     UNITY_DEFINE_INSTANCED_PROP(half4, _Color)
6. UNITY_INSTANCING_BUFFER_END(Props)
7.  
8. UNITY_INSTANCING_BUFFER_START(EmissionProps)
9.     UNITY_DEFINE_INSTANCED_PROP(half4, _EmissionColor)
10. UNITY_INSTANCING_BUFFER_END(EmissionProps)