P4
On macOS, /usr/bin/tidy -version reports
HTML Tidy for Mac OS X released on 31 October 2006 - Apple Inc. build 2649
which is very (very) old. It is generally better to use a newer version, such as installed by HomeBrew in either /opt/homebrew/bin/tidy or /usr/local/bin/tidy.
$ which tidy
/usr/local/bin/tidy
$ tidy --version
HTML Tidy for Apple macOS version 5.6.0
HTML Tidy for Mac OS X released on 31 October 2006 - Apple Inc. build 2649
which is very (very) old. It is generally better to use a newer version, such as installed by HomeBrew in either /opt/homebrew/bin/tidy or /usr/local/bin/tidy.
$ which tidy
/usr/local/bin/tidy
$ tidy --version
HTML Tidy for Apple macOS version 5.6.0
