perl -MHTTP::Tiny -MMIME::Base64 -e 'print qq~<link href="data:image/x-icon;base64,\n~, encode_base64(HTTP::Tiny->new->get($ARGV[0])->{content},"\n"), qq~"  rel="icon" type="image/x-icon">\n~||die"something went wrong"' https://www.perl.com/favicon.ico