You probably mean this one: https://spyware.neocities.org/articles/firefox

But the article is total garbage, Firefox is totally fine to use. If you want something better, check out LibreWolf, it removes the telemetry, Sponsored sites, Pocket, etc. and adds privacy features. It also comes with uBlock Origin preinstalled. They even have an official Lemmy community: !librewolf@lemmy.ml