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       $time = XenForo_Application::$time;
     
        // CHRISTMAS (1ST DEC - 7TH JAN)
        $christmasStart = mktime(0, 0, 0, 12, 1, date('Y'));
        $christmasEnd = mktime(23, 59, 59, 12, 1, date('Y'));
        $christmas1Start = mktime(0, 0, 0, 1, 1, date('Y'));
        $christmas1End = mktime(23, 59, 59, 1, 7, date('Y'));
     
        if ($christmasStart <= $time && $christmasEnd >= $time) {
            return "showChristmasHeader";
        } else if ($christmas1Start <= $time && $christmas1End >= $time) {
            return "showChristmasHeader";
        }