YES! I remembered something about extend, but couldn't find it anywhere. That solved my problem.
It might be a good idea to add that to the doc string for `org-src-block-faces`, maybe with some version note that it applies to.
Thanks so much!
John
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Professor John Kitchin (he/him/his)
Doherty Hall A207F
Department of Chemical Engineering
Carnegie Mellon University
Pittsburgh, PA 15213
412-268-7803