Well, your regex doesn't mention newlines :/)
your data has newlines
all that dumpoff stuff has newlines in between
its like whitespace :)
add that ( [\r\n ]+ ) to your pattern

And quotemeta 

use Path::Tiny qw/ path /;
my $raw   = path( $file )->slurp_raw;
my $re = qr{
\Q$dumpoff $end\E
[\r\n ]+
(\#[\d]+)
[\r\n ]+
\Q$dumpon $end\E
[\r\n ]+
(.*?)
\#[\d]+
}sx;

while( $raw =~ m/$re/g ){
    my( $id, $tidy ) = ( $1, $2 );
    ...
}

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In reply to Re: extract text from multi-line context by Anonymous Monk
in thread extract text from multi-line context by herman4016

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