I don't remember Mozilla saying that. There were voices of suspicion, though, following the decision to disable loading of userChrome.css by default, allegedly

I don't remember Mozilla saying that. There were voices of suspicion, though, following the decision to disable loading of userChrome.css by default, allegedly for performance reasons. https://www.ghacks.net/2019/05/24/firefox-69-userchrome-css-and-usercontent-css-disabled-by-default/ https://www.ghacks.net/2019/05/24/firefox-69-userchrome-css-...