https://git.zabbix.com/projects/ZBX/repos/zabbix/browse/ui/app/views/template.list.php#307

see "templates.list" there, while we do not have such destination currently.
Proper would be "template.list"  (without "s").

I could not reproduce it myself, but I have reports that if zabbix frontend is hasted using  "ingress + load balancer", this (under some conditions) may end up by visiting the "templates.list" page which gives error "Page not found"