$ not_utf8="$( printf "\x96" )"

$ perl -e"use utf8; q{$not_utf8}"
Malformed UTF-8 character: \x96 (unexpected continuation byte 0x96, with no preceding start byte) at -e line 1.
Malformed UTF-8 character (fatal) at -e line 1.

##</code><code>##

$ printf "\x96" | perl -nle'
   use open ":std", ":utf8";
   printf "%vX\n", $_;
'
Malformed UTF-8 character: \x96 (unexpected continuation byte 0x96, with no preceding start byte) in printf at -e line 1, <> line 1.
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