Show the issue. Here is the add-on I use to see the load time. https://addons.mozilla.org/en-US/firefox/addon/load-time/ Provide example sites that are slow for you. Who are you using for DNS? Try this tool to see if you can get a better provider. https://www.grc.com/files/DNSBench.exe

Absolutely all sites load several times slower. It seems that Firefox somehow slows down the speed of communication. One day, everything just started to slow down. Although I did not install or change anything in the system. This is not at all clear to me. Instead, Edge and Opera work without changes. So the problem is not in the provider, not in the network. Something happened with Firefox. Or the system (I have Windows 11) slows down the browser, is this possible?

Still no evidence of the issue.... Good luck.

Sorry. I didn't understand right away. English is not my native language. Here are screenshots of the loading speed of some sites. Only one page was loaded each time. There were no other active connections. It is not clear with the benchmark, as if the firewall did not block it. Maybe I'll figure it out later. And screenshots of the speed test comparison in Firefox and Edge. Thank you.

Thanks. Where are you? Your dns does look slow. Who is your DNS provider?

I'm from Ukraine. Look at the screenshots, what I could find. Is this information enough? DNSBench can't connect, I don't understand why. https://who.is/ finds only the IP. Or I can't figure it out... I also want to outline the problem once again. Firefox worked fine, but about a week ago it started to slow down when loading any pages. While other browsers work fine. Comparing speed tests in Firefox and Edge revealed an abnormally high ping in Firefox - 198 ms in Firefox versus 6 ms in Edge. Upload speed is also low. 16 mbit versus 97 mbit. My tariff plan with my provider just provides for speeds up to 100 mbit, so I don't think the problem arose because of the provider. Thank you for your understanding and your time.