What potential server settings could cause tabulators to be sent in a PHP request?

Tabulators being sent in a PHP request could be caused by the server's `magic_quotes_gpc` setting being turned on. This setting automatically escapes certain characters, including tabulators, in incoming request data. To prevent tabulators from being sent, you can disable `magic_quotes_gpc` in your server settings or use `stripslashes()` function to remove the escaping when processing the request data.

// Disable magic_quotes_gpc setting
if (get_magic_quotes_gpc()) {
    function stripslashes_deep($value) {
        $value = is_array($value) ? array_map('stripslashes_deep', $value) : stripslashes($value);
        return $value;
    }

    $_POST = array_map('stripslashes_deep', $_POST);
    $_GET = array_map('stripslashes_deep', $_GET);
    $_COOKIE = array_map('stripslashes_deep', $_COOKIE);
    $_REQUEST = array_map('stripslashes_deep', $_REQUEST);
}