This blog is updated daily.
A general description is here.
Where characters are attempted to be plotted by ‘pdf()’ and ‘postscript()’ which are not in the selected 8-bit character set (most often Latin-1) and the R session is using a UTF-8 locale, the warning messages will show the UTF-8 character rather than its bytes and one dot will be substituted per character rather than per byte. (Platforms whose ‘iconv()’ does transliteration silently plot the transliteration.)
In a UTF-8 locale some transliterations are now done without warning (e.g., dashes and Unicode minus to hyphen, ligatures are expanded and Euro sign replaced by ‘EUR’ except if using ‘encoding + "WinANSI"’, the default on Windows).
If the ‘libdeflate’ library and headers are available, ‘libdeflate’ rather than ‘libz’ is used to (de)compress R objects in lazy-load databases, Typically tasks spend up to 5% of their time on such operations, although creating lazy-data databases is one of the exceptions.
This can be suppressed if the library is available by the ‘configure’ option ‘--without-libdeflate-compression’.
‘list.files()’ on Windows now returns also files with names longer that 260 bytes (the Windows limit is 260 characters). Previously, some file names particularly with ‘East Asian’ characters were omitted.
‘readChar(useBytes=TRUE)’ now terminates strings even when the underlying connection uses extra space in the input buffer. This fixes problems with extra garbage seen with ‘gzip’ connections, PR#18605.
Named capture in PCRE regular expressions now works also with more than 127 named groups (PR#18588).
Datetime functions are now robust against long jumps when dealing with internal time zone changes. This avoids confusing warnings about an invalid time zone, previously triggered by turning warnings into errors or handling them via ‘tryCatch’ (PR#17966, PR#17780).
Datetime functions now restore even an empty ‘TZ’ environment variable after internal time zone changes (PR#17724). This makes results of datetime functions with this (typically unintentional) setting more predictable.