Some sites do not work correctly even if I select Custom and uncheck the boxes there, but these sites work in Google Chrome. One of the examples is the Twitch site. It's not displayed correctly in some places and there are probably other sites. I wouldn't want to add these sites manually, because personally I don't see any point in it for myself. I really hope that Mozilla has provided the ability to completely disable this function using standard tools (settings or about:config), without installing any extensions.

Thank you!