Using a link from old development code can be outdated.
Just look at the current documentation:
Modify components of a theme — theme • ggplot2 (tidyverse.org)
strip.background controls what you want.
Using a link from old development code can be outdated.
Just look at the current documentation:
Modify components of a theme — theme • ggplot2 (tidyverse.org)
strip.background controls what you want.