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The non-default ‘method = "internal"’ is deprecated for ‘http://’ and ‘ftp://’ URIs for both ‘download.file’ and ‘url’.
On Windows, ‘method = "wininet"’ is deprecated for ‘http://’, ‘https://’ and ‘ftp://’ URIs for both ‘download.file’ and ‘url’.
For ‘ftp://’ URIs the default method is now ‘"libcurl"’ if available (which it is on CRAN builds).
‘method = "wininet"’ remains the default for ‘http://’ and ‘https://’ URIs but if ‘libcurl’ is available, using ‘method = "libcurl"’ is preferred.
The character-classification functions used (by default) to replace the system ‘iswxxxxx’ functions on Windows, macOS and AIX have been updated to Unicode 13.0.0.
The character-width tables have been updated to include new assignments in Unicode 13.0.0. This included treating all control characters as having zero width.