You can specify your own error message like so(from the CGI::Carp docs):

use CGI::Carp qw(fatalsToBrowser set_message);

BEGIN {
   sub handle_errors {
      my $msg = shift;
      print "<h1>Oh gosh</h1>";
      print "Got an error: $msg";
  }
  set_message(\&handle_errors);
}
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This will catch all errors and this may not be the desired behavior.

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