Zabbix screens no longer support the possibility to display another screen as a screen element. After the upgrade, all screen cells containing another screen will be empty.
The format of host/template export in XML/JSON has been changed. For more details, see What's new in 4.4.0.
Realtime fields have been split from the
items table into a new table called
item_rtdata. See also What's new in 4.4.0.