Uniform buffers are disabled on Chrome for Mac, but eg you can set disableUniformBuffers to false like on line 35 and then the PG works for me on Chrome on my Macbook. 
EDIT: but IDK under what conditions the performance might tank… 
PS just for reference, it’s this PR that disabled uniform buffers for Chrome/Mac. IIRC it was because large GLB models were loading much slower with them enabled. EDIT: here’s the forum thread where it fixed the slow loading issue for reference.