Code highlighting is not working for me at all on MacOS 11.1 Big Sur with the RStudio IDE either 1.4 or 1.3.
I tried to reset the state of the IDE with
open ~/.rstudio-desktop from the terminal, but it said that the item did not exist.
As you can see from the screenshots below, light themes have no highlighting, while dark themes like the material theme change the background but not the text.
Any help would be greatly appreciated.