R help - Jul 2017 - cannot use package RcmdrPlugin.plotByGroup

Greetings,

I am a new use of R, starting from R-commander.

I find that the default quantile-comparison (Q-Q plot) of R-commander
has no group option, and I happened to notice RcmdrPlugin.plotByGroup in
the packages list. As the name is so explicit, I installed it, loaded
it, R-commander restarted, but the 3 menu item under Graphs->plot by
group are all greyed out. What could be wrong?

-- 
Regards,
Lu Wei
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