Hi mslack,
The reason we ask for you to submit a testbed is to look directly at what you use. That is code and assets, because that makes it easy for us to rule out if the error is in the code/assets. You submitted a bug report with a config.lua file. So please, do submit a complete bug report with sample code and the assets you are using, that create the artifact. Or append that to your existing bug (21961).
Thanks.
Alex