Use ML to create dark themes / light themes / themes that match the users theme.
make a big database of them, let me choose from a drop down when I visit the site.
impove theming in general.
I just want to change the palette, the themes in the Themes search often don't follow the system, or work bad in dark modes, and tweaking them is a nightmare.
look at the Firefox Colour extension and build that straight in but make it better, the UX is not good.