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strsplit(*, fixed=TRUE), potentially iconv() and internal string formatting is now faster for large strings, thanks to report PR#9902 by John Brzustowski.
plot(fn, xlim=c(a,b)) would not set "from" and "to" properly when plotting a function.
old.packages, and hence update.packages, incorrectly handled duplicate packages when multiple package repositories are specified. The first package encountered was selected, not the one with highest version number. This has been fixed.