in reply to HTTPS returning 400 from Linux but 200 OK from Windows

You can try below,
$ua->credentials( $linktologin, $pause, $username, $password ); Eg. $ua->credentials( 'https://google.com/:443', 'PAUSE', ‘$username +’, ‘$password’);

You can refer below link for more details, https://perlmaven.com/lwp-useragent-and-basic-authentication

Replies are listed 'Best First'.
Re^2: HTTPS returning 400 from Linux but 200 OK from Windows
by marto (Cardinal) on Jan 27, 2017 at 14:59 UTC

    https://google.com/:443 isn't a valid URL, even if it were Google wouldn't identify as 'PAUSE'. If you're going to copy and paste an example, it doesn't make sense to edit it so that it doesn't work.