Zabbix Dashboard not showing Action box on top of other popups.

[TheCookieMonster]

On the Zabbix Dashboard
If I click on a problem, then on the host, the popup window that appears, with scripts that can be ran, is not brought to the front (example pic below)



I did try uninstalling the Zabbix Frontend, then installing is again, but this did not make any difference.
This issue is the same, regardless of what user logs into Zabbix Frontend, and regardless of what browser they are using (chrome, firefox, ie etc...)

Does anyone know how I can fix this?

I can running Zabbix 4.2 on Ubuntu 18.04.2 LTS

[TheCookieMonster]

Still got this issue, also now on Zabbix 4.4, on CentOS 7.6.
I've actually got this issue on 4 different Zabbix systems, so im shocked no-one else has seen this problem