R or RStudio on OX X 10.9 suddenly request X11 installation

Question

Since some days I always get a message when working with R and RStudio, telling that "to open R, you must install X11". This is strange because I'm working since "ages" with R and RStudio, and also the current configuration (R 3.1.2 and RStudio 0.99.283 on OS X 10.9.5) runs since some weeks without any troubles.

Does anybody know what I could do? Reinstall R / RStudio?

Answer 1

Coincidentally, I stumbled over an ggplot2-issue at GitHub, which might explain the behaviour (a bug in the colorspace package).

I'll try to install the previous version on my Mac later and check whether this really solves the problem...