Firefox is very slow/unable to load specific pages after laptop reset

Hi hi, I just did a complete reset to factory settings of my laptop (MSI), and a wipe of my hard drives too. After reinstalling Firefox (literally the first thing I did after setting up windows), it runs more slowly than before the reset (even for a basic search on Google/Duckduckgo). I am also unable to load any pages under the domain discussions.unity.com : the page loads forever, it's impossible to click on anything (even the hovering styles don't work), and I get a banner at the top of the screen that says "This page is slowing down Firefox. To speed up your browser, stop this page.". Also the memory usage for this page skyrockets (gone up to 4000MB??). I've disabled the 2 extensions I have (Dark Reader and Adblock Plus), restarted Firefox, restarted the computer, cleared the cache, even turned off the mozilla syncing, nothing worked. Any idea on what could be happening here? It's the first time in using Firefox for over 15 years that I've seen this happened. Thank you for your time and attention <3