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On Windows, ‘download.file(method = "wininet") ’is deprecated for ‘ftp://’ URIs and will be removed in R 4.2.0. It remains the default but if ‘libcurl’ is available, use ‘method = "libcurl"’.
Use of ‘ftp://’ URIs should be regarded as deprecated, with on-going support confined to ‘method = "libcurl"’ and not routinely tested. (Nowadays no major browser supports them.)