Like X-Minimum-Recommended-Age or X-Contains-Content-Themes: violence, nudity
Then website authors could flag those things and leave it at that. And parents could actually tell the browser to set allowed content ratings and just refuse to load a page if it gets a header that doesn't match.
That would preserve privacy and all websites would have to do would be to implement a few headers.
I think YT already makes you specify the audience for a video. that would allow us to block certain content without having to block youtube altogether, for example.
RamblingCTO•2d ago