How can I revert back from v6?

[PromoFaux]

OK super - thanks, that absolutely confirms my hypothesis.

So the issue here is that you're using the https:// interface rather than the http:// one. This isn't your fault. When you upgraded, the following things should have happened:

• A dialog would have been shown asking if you wanted to disable lighttpd, as it is no longer needed
• If you selected yes (the recommended option) it should have carried on as normal and bound the new web interface to port 80. If you selected no it would have bound the web interface to port 8080.

This is described in the announcement post, specifically:

@PromoFaux

During the upgrade operation, you will be presented with a dialog box asking if you wish to disable lighttpd. Doing so is probably appropriate for most users – unless you are using it to host web pages other than Pi-hole’s, in which case you may choose to keep it enabled. With lighttpd disabled, pihole-FTL will attempt to bind to ports 80 for HTTP and 443 for HTTPS. If there is any conflict on these ports, then it will revert to port 8080 for HTTP.

I've seen a few instances where it has defaulted to port 8080 unexpectedly - and we're still trying to get to the bottom of that, and I can see from your debug token that the plain HTTP interface has indeed defaulted to port 8080. however there are two things you can try to see if there are any improvements:

• Browse instead to http://192.168.2.254:8080/admin
• Try to set the default behaviour with pihole-FTL --config webserver.port "80o,[::]:80o,443so,[::]:443so" and then browse to http://192.168.2.254/admin (note the difference between http and https)

Something we have noted is that on some older hardware, the HTTPS interface can be very slow due to the increased load on encrypting each request.

If you are only accessing the interface internally, there is no need for HTTPS so you can use the HTTP one instead - this should be much faster for you!