The second pair in confusables.php should not be part of the array because it is the inverse of the 1309th pair. This results in them reversing each other depending on which of the "from" values is present in the string provided. The 1309th pair is the valid one of the two as its replacement value is also used in other instances of exclamation point lookalikes (for example in pairs 1304 ('⁈'=>'ʔǃ'), 1310 ('！'=>'ǃ'), 1311('⁉'=>'ǃʔ'), 1312('‼'=>'ǃǃ')). To clarify, the KEY in the second pair is the clean string.

Here's a quick script that I wrote to prove that it's happening:

<?php

define('IN_PHPBB', true);

$phpbb_root_path = './';

$phpEx = substr(strrchr(__FILE__, '.'), 1);

include($phpbb_root_path . 'common.' . $phpEx);

$homographs = include($phpbb_root_path . 'includes/utf/data/confusables.' . $phpEx);

$i = 1;

foreach ($homographs as $from => $to)

{

// Is the value getting reversed?

if (utf8_clean_string($to) == $from)

{

echo "Reversal happening at pair $i- $from : $to <br />";

}

// Check if value from pair 1309 exists

if (utf8_strpos($to, 'ǃ') !== false)

{

echo "1309 value appears at $i <br />";

}

$i++;

}

?>

It also seems to happen at pair 518, but that seems to be because the key and the value are the same character?