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[Sarog]

Good day!
I use zabbix_server (Zabbix) 4.2.3
I have this error, when trying to input in zabbix.

I tried to find out what was wrong, and in this file '/usr/share/zabbix/index.php' variable $page
var_dump($page);
( [title] => ZABBIX [file] => index.php [scripts] => [type] => [menu] => ) but in /include/classes/mvc/CView.php
/include/views/general.login.php
...
/include/menu.inc.php

var_dump($page) NULL
and

if (!$page_exists && $page['type'] != PAGE_TYPE_XML && $page['type'] != PAGE_TYPE_CSV && $page['type'] != PAGE_TYPE_TEXT_FILE) { $denied_page_requested = true; } return $denied_page_requested; //return false if i write this code on top /include/views/general.login.php, all works fine
$page = $GLOBALS['page'];

Please, what I done wrong.
Thank you!