Is there a way to set session-specific background colors or themes? I am frequently working on several related or completely unrelated projects, and the ability to color-code the sessions in either the Windows R-Gui or the MacOS/Linux consoles makes "visual grepping" much easier and faster ("visual grepping" is from the description of the file-icons package for the Atom editor). Themes are great, but when I change it for one session it changes for all sessions. Please excuse any oversights on my part, and thanks!
Unfortunately, this is not currently possible. You might consider filing this as a feature request at https://github.com/rstudio/rstudio/issues.
Thank you, Kevin. I just entered issue #2350 as a feature request.