It looks like the content plugin is out of date. Facebook no longer supports color scheme for the Like Button. I will add an issue to our tracker to delete the removed parameters, but for now, you can ignore the setting as it will not work.
Strike that. Re-reading the documentation - it was not removed. I must need sleep
Could you tell me a specific URL where you're seeing the behavior?
-Melissa
Content Plugin - Like Dark theme does not work
