Since moving to Grid v2.5 we offer R v3.5.1 centrally, which might be more new than what you have in your home directory. And the RStudio launch script from the NoMachine drop-down menu will run our centrally-installed RStudio (also newer).
If you had used a local R install (== miniconda in your home folder), to transition to the central one, you'll need to do the following:
1) if your .bashrc or .bash_profile had a command to export the RSTUDIO_WHICH_R, please comment out this line and then restart all...
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