http://qs1969.pair.com?node_id=576661

perl -CSAD -wE 'use utf8; use v5.16; my $ss =q{ss}; my $sz = q{ß}; my $css = q{SS}; my $csz = q{ẞ}; my $mss = q{sS}; my $ssm = q{Ss}; foreach my $o ($sz, $ss, $css, $csz, $mss, $ssm) { foreach my $i ($sz, $ss, $css, $csz, $mss, $ssm) { print qq{$o and $i : }; if ( fc($o) eq fc($i) ) { print q{equal} } else { print qq{not}}; print qq{\n};'}} ß and ß : equal ß and ss : equal ß and SS : equal ß and ẞ : equal ß and sS : equal ß and Ss : equal ss and ß : equal ss and ss : equal ss and SS : equal ss and ẞ : equal ss and sS : equal ss and Ss : equal SS and ß : equal SS and ss : equal SS and SS : equal SS and ẞ : equal SS and sS : equal SS and Ss : equal ẞ and ß : equal ẞ and ss : equal ẞ and SS : equal ẞ and ẞ : equal ẞ and sS : equal ẞ and Ss : equal sS and ß : equal sS and ss : equal sS and SS : equal sS and ẞ : equal sS and sS : equal sS and Ss : equal Ss and ß : equal Ss and ss : equal Ss and SS : equal Ss and ẞ : equal Ss and sS : equal Ss and Ss : equal