Missing text in graphs after upgrade to 4.0.8

Steps to reproduce:

1. CentOS/OEL/RHEL 6.X/7.X
2. From Zabbix repo install & configure Zabbix Frontend ver. 4.0.7 (zabbix-web-pgsql-4.0.7-1.el7.noarch)
3. Upgrade to Zabbix Frontend ver. 4.0.8 (zabbix-web-pgsql-4.0.8-1.el7.noarch)

Result:
After upgrade from 4.0.7 to 4.0.8 there is no text in any graph. See attached files.