But you told it to match the string chr12! You can't place code in a string literal and expect it to be executed.

You want any of the following:

s/\014//g;            # By octal
s/\x0C//g;            # By hex
s/\x{C}//g;           # By hex (leading zeros allowed)
s/\N{U+C}//g;         # By hex (leading zeros allowed)
s/\N{FORM FEED}//g;   # By name
s/\N{FF}//g;          # By alias
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You could also use the character literally.

my $ff = chr(12);
s/\Q$ff\E//g;
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