Slow loading sites on Unifi Equipment

I have a new network setup and am I'm trying to get my new pi-hole working. My equipment is: Ubiquiti USG (router/firewall), 8-port managed switch, and AP AC Lite. Pi-hole is on subnet 192.168.1.x along with the USG.

I don't believe that there is an issue with the communication on the network and the pi-hole.

When I connect to websites the typical behavior is that non-blocked items are loading, then blocked items will sit and try to connect until they timeout. Below is the Chrome inspector from pi-hole's ad page as an example.

I did change the iptables per previous posts on the forum and did not see any change in behavior. I have ipv6 disabled on my modem and by default the unifi equipment does have ipv6.

Debug Token:

9nrsxtqcdm

What does the Timing tab look like on one of those blocked requests?

Sorry, I’m not sure exactly what you mean by the timing tab.

The two blocked JavaScript items are connections that timed out after 22 seconds.

If you click on one of the requests in the dev tools (such as in your screenshot), it opens up with the request information, including a tab called Timing.

If you try to connect to the web interface over https, does it time out?

Ok thanks.Here is the timing tab:

Yes the web interface times out if I try to connect via https.

Do you have custom firewall rules in place? What is the output of the following two commands?

sudo iptables -L
sudo ip6tables -L

I do, here are the current rules.

Have you seen this already?

Do you have a Linux computer (not the Pi-hole itself) at hand that shows these slow loading problems?

If so, please run

nmap --reason pi.hole -p443          # for TCP
sudo nmap --reason pi.hole -p443 -sU # for UDP

I get:

PORT    STATE  SERVICE REASON
443/tcp closed https   conn-refused

PORT    STATE  SERVICE REASON
443/udp closed https   port-unreach ttl 64

and that with and without any firewall rules on my Pi-hole.