[Error] 
Call to undefined function Bitrix\Main\Text\mb_strpos() (0)
/home/bitrix/www/bitrix/modules/main/lib/text/binarystring.php:58
#0: Bitrix\Main\Text\BinaryString::getPosition(string, string, integer)
	/home/bitrix/www/bitrix/modules/main/lib/page/asset.php:2359
#1: Bitrix\Main\Page\Asset::cutSourceMap(string)
	/home/bitrix/www/bitrix/modules/main/lib/page/asset.php:2257
#2: Bitrix\Main\Page\Asset->optimizeAsset(array, boolean, string, string, string, string)
	/home/bitrix/www/bitrix/modules/main/lib/page/asset.php:1566
#3: Bitrix\Main\Page\Asset->getCss(integer)
	/home/bitrix/www/bitrix/modules/main/classes/general/main.php:702
#4: CAllMain->GetCSS(integer, boolean)
	/home/bitrix/www/bitrix/modules/main/classes/general/main.php:3180
#5: CAllMain->EndBufferContent(string)
	/home/bitrix/www/bitrix/modules/main/classes/general/main.php:3139
#6: CAllMain->EndBufferContentMan()
	/home/bitrix/www/bitrix/modules/main/include/epilog_after.php:36
#7: require(string)
	/home/bitrix/www/bitrix/modules/main/include/epilog.php:3
#8: require_once(string)
	/home/bitrix/www/bitrix/footer.php:4
#9: require(string)
	/home/bitrix/www/about/contacts/index.php:631