برای حل مشکل محتوای زیر را در فایل  /public_html/language/fa-IR/localise.php جایگزین کنید.

defined('_JEXEC') or die;

use Joomla\CMS\Date\Date;

abstract class Fa_IRLocalise {

    public static function getPluralSuffixes($count) {
        if ($count == 0) {
            $return =  array('0');
        }
        elseif($count == 1) {
            $return =  array('ONE', '1');
        }
        else {
            $return = array('OTHER', 'MORE');
        }
        return $return;
    }

    public static function getIgnoredSearchWords() {
        $search_ignore = array();
        $search_ignore[] = "and";
        $search_ignore[] = "in";
        $search_ignore[] = "on";
        return $search_ignore;
    }

    public static function getLowerLimitSearchWord() {
        return 3;
    }

    public static function getUpperLimitSearchWord() {
        return 20;
    }

    public static function getSearchDisplayedCharactersNumber() {
        return 200;
    }
}


class fa_IRDate extends Date {
    const DAY_NUMBER	= "\x027\x03";
    const DAY_NUMBER2	= "\x030\x03";
    const DAY_YEAR		= "\x032\x03";
    const MONTH_ABBR	= "\x033\x03";
    const MONTH_NAME	= "\x034\x03";
    const MONTH_NUMBER	= "\x035\x03";
    const MONTH_NUMBER2	= "\x036\x03";
    const MONTH_LENGTH	= "\x037\x03";
    const YEAR_ABBR		= "\x040\x03";
    const YEAR_NAME		= "\x041\x03";
    const AM_LOWER		= "\x042\x03";
    const AM_UPPER		= "\x043\x03";
    const PERSIAN_EPOCH	= 1948320.5;

    protected static $month_names	= array("فروردين","ارديبهشت","خرداد","تیر","مرداد","شهریور","مهر","آبان","آذر","دی","بهمن","اسفند");

    public function calendar($format, $local = false, $translate = true)
    {
        // Replace format strings that can be translated.
        $format = preg_replace('/(^|[^\\\])d/', "\\1".self::DAY_NUMBER2, $format);
        $format = preg_replace('/(^|[^\\\])j/', "\\1".self::DAY_NUMBER, $format);
        $format = preg_replace('/(^|[^\\\])z/', "\\1".self::DAY_YEAR, $format);
        $format = preg_replace('/(^|[^\\\])M/', "\\1".self::MONTH_ABBR, $format);
        $format = preg_replace('/(^|[^\\\])F/', "\\1".self::MONTH_NAME, $format);
        $format = preg_replace('/(^|[^\\\])n/', "\\1".self::MONTH_NUMBER, $format);
        $format = preg_replace('/(^|[^\\\])m/', "\\1".self::MONTH_NUMBER2, $format);
        $format = preg_replace('/(^|[^\\\])t/', "\\1".self::MONTH_LENGTH, $format);
        $format = preg_replace('/(^|[^\\\])y/', "\\1".self::YEAR_ABBR, $format);
        $format = preg_replace('/(^|[^\\\])Y/', "\\1".self::YEAR_NAME, $format);
        $format = preg_replace('/(^|[^\\\])a/', "\\1".self::AM_LOWER, $format);
        $format = preg_replace('/(^|[^\\\])A/', "\\1".self::AM_UPPER, $format);

        // Format the date using parent method.
        $return = parent::calendar($format, $local);

        // Convert to Jalali date.
        $jd = gregoriantojd($this->month, $this->day, $this->year);
        $jalaliDate = self::jd_to_persian($jd);
        $m = $jalaliDate['mon'];
        $d = $jalaliDate['day'];
        $y = $jalaliDate['year'];

        // Replace placeholders with Persian values.
        if (strpos($return, self::DAY_NUMBER) !== false) {
            $return = str_replace(self::DAY_NUMBER, $d , $return);
        }
        if (strpos($return, self::DAY_NUMBER2) !== false) {
            $return = str_replace(self::DAY_NUMBER2, sprintf("%02d",$d), $return);
        }
        if (strpos($return, self::DAY_YEAR) !== false) {
            $return = str_replace(self::DAY_YEAR, $jd - self::persian_to_jd(1,1,$y)+1, $return);
        }
        if (strpos($return, self::MONTH_ABBR) !== false) {
            $return = str_replace(self::MONTH_ABBR, self::$month_names[$m-1] , $return);
        }
        if (strpos($return, self::MONTH_NAME) !== false) {
            $return = str_replace(self::MONTH_NAME, self::$month_names[$m-1] , $return);
        }
        if (strpos($return, self::MONTH_NUMBER) !== false) {
            $return = str_replace(self::MONTH_NUMBER, $m , $return);
        }
        if (strpos($return, self::MONTH_NUMBER2) !== false) {
            $return = str_replace(self::MONTH_NUMBER2, sprintf("%02d", $m) , $return);
        }
        if (strpos($return, self::MONTH_LENGTH) !== false) {
            $return = str_replace(self::MONTH_LENGTH, ($m < 7 ? 31 : (($m < 12 ? 30 : self::leap_persian($y)) ? 30 : 29)) , $return);
        }
        if (strpos($return, self::YEAR_ABBR) !== false) {
            $return = str_replace(self::YEAR_ABBR, sprintf("%02d",$y % 100), $return);
        }
        if (strpos($return, self::YEAR_NAME) !== false) {
            $return = str_replace(self::YEAR_NAME, $y, $return);
        }
        if (strpos($return, self::AM_LOWER) !== false) {
            $return = str_replace(self::AM_LOWER, $this->format('a',$local)=='pm' ? 'ب ظ' : 'ق ظ', $return);
        }
        if (strpos($return, self::AM_UPPER) !== false) {
            $return = str_replace(self::AM_UPPER, $this->format('a',$local)=='pm' ? 'ب ظ' : 'ق ظ', $return);
        }

        return $return;
    }

    /**
     * Converts a Julian Day to a Persian (Jalali) date.
     */
    public static function jd_to_persian($jd)
    {
        $depoch = $jd - self::persian_to_jd(1, 1, 475);
        $cycle = floor($depoch / 1029983);
        $cyear = $depoch % 1029983;

        if ($cyear == 1029982) {
            $ycycle = 2820;
        } else {
            $aux1 = floor($cyear / 366);
            $aux2 = $cyear % 366;
            $ycycle = floor(((2134 * $aux1) + (2816 * $aux2) + 2815) / 1028522) + $aux1 + 1;
        }

        $year = $ycycle + (2820 * $cycle) + 474;
        if ($year <= 0) {
            $year--;
        }

        $yday = ($jd - self::persian_to_jd(1, 1, $year)) + 1;
        $month = ($yday <= 186) ? ceil($yday / 31) : ceil(($yday - 6) / 30);
        $day = ($jd - self::persian_to_jd($month, 1, $year)) + 1;

        return array('year'=>$year, 'mon'=>$month,'day'=> $day);
    }

    /**
     * Converts a Persian (Jalali) date to Julian Day.
     */
    public static function persian_to_jd($month, $day, $year)
    {
        $epbase = $year - (($year >= 0) ? 474 : 473);
        $epyear = 474 + $epbase % 2820;

        return $day +
               (($month <= 7) ? (($month - 1) * 31) : ((($month - 1) * 30) + 6)) +
               floor((($epyear * 682) - 110) / 2816) +
               ($epyear - 1) * 365 +
               floor($epbase / 2820) * 1029983 +
               self::PERSIAN_EPOCH;
    }

    /**
     * Checks if a Persian year is a leap year.
     */
    public static function leap_persian($year)
    {
        return (((((($year - (($year > 0) ? 474 : 473)) % 2820) + 474) + 38) * 682) % 2816) < 682;
    }
}