Thanks Nicolas. I’m not using any child themes, so that is definitely not the issue. Based on additional testing, it appears to be caused by one of the following plugins: Yoast SEO, Nextgen, Monster Insights, Akismet, or Jetpack.
I haven’t had time to debug all of these yet, but the error started showing up again after disabling all plugins, then going back and installing these four.
I’ll post an update if I am able to isolate the specific plugin causing the conflict for future reference.
Thanks for a great theme!
cheers,
chris