Turning off automatic dark mode with a dark editor palette

Maybe I'm one of the weird ones, but I prefer RStudio running in light mode, but with the console and the editor using a dark palette. In the past, this used to be possible by choosing the Classic theme under Appearance in the Options, but in a recent RStudio release, Classic was removed, meaning that if I choose a dark editor palette, RStudio also flips into dark mode. This page says that dark mode is a superset of the Modern and Sky themes that is automatically activated when a dark palette theme is chosen.

Is there a way to turn this automatic activation behavior off, so I can have light mode with a dark editor palette?

There's no longer any officially supported way to do this, but it isn't impossible. You can read instructions here (also, upvote the issue!):