I'm trying to figure out how to get viewport reflections working in Houdini 17.5.258

I have a sphere with a principled shader with
Metallic = 1
Reflectivity = 1
Roughness = 0

I also added a parm with the name “GL Reflect” and set it to 1

I have lights in the scene, I have “Enable Reflections” and “HDR Reflections” ticked in the Display Options.
The reflection map size is 512x512.

I click on “High Quality Lighting with Shadows” and the sphere doesn't show any reflected objects.
I tried this in the OpenGL rop with the same results.

Am I missing something here?

I guess I should also add I'm on OSX 10.13.6

Reflections requires a GL implementation to have 32 texture samplers available, which MacOS doesn't currently have. I think this is fixed in the next version of Houdini though.