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!