Action for redaxo CMS which escapes \r,\f,\n only for latex code in square brackets \[ \].

rex_action_keep-latex.php

<?php
// escape \r,\f,\n in latex code in square brackets \[ \]
$REX_ACTION['VALUE']['1']=preg_replace_callback(
    '#\\[(.+?)\\]#s',
    function ($matches) {
        $search = array('\\n','\\r','\\f');
        $replace = array('\\\\n','\\\\r','\\\\f');
        return str_replace($search, $replace, $matches[0]);
    },
        $REX_ACTION['VALUE']['1']);
?>