I can reproduce, but only on export - it works fine in Firefox, Chrome and Node-Webkit in preview, but breaks on export, even with script minification disabled. I can't imagine why. In theory the exported code is identical to the preview mode, especially with minification disabled. I still can't rule out driver bugs or problems with the browser's recompilation of the shaders for security reasons... it's possible the latest drivers are still borked, especially since it seems to randomly work for some. But then I don't know why preview mode would work.
I can reproduce on an nVidia GeForce GTX 660. What hardware does/doesn't it reproduce on?