Full Message: WARNING: AllowZoneDrifting is enabled. This is considered an insecure configuration option. It will be removed in a future release. Please consider disabling it now.
Action Performed:
$ systemctl status firewalld -l --no-pager
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Jul 02 08:40:13 nextor firewalld[898]: WARNING: AllowZoneDrifting is enabled. This is considered an insecure configuration option. It will be removed in a future release. Please consider disabling it now.
Fix/Solution:
Edit /etc/firewalld/firewalld.conf
Change
AllowZoneDrifting=yes to AllowZoneDrifting=no
Reload the service.
$ sudo firewall-cmd --reload