1861362 - Stop exposing system accent color by default

Status: NEW

(Core :: Widget, task, P3)

Description

[Martin Thomson [:mt:]]

This has some trade-offs, but I think that the balance of privacy vs. utility is off here.

On systems where widget.non-native-theme.use-theme-accent is true (all except Windows currently), this is quite visible in terms of form controls and highlight colors. That increases the feeling that Firefox is integrated with the system.

However, exposing this to content provides many bits of fingerprinting entropy. People do customize their phones with themes. Highlight colors are often derived from either the theme or things like the choice of home screen background image. This won't be the full 24 bit color depth, but it's not as little as the other accessibility things we expose (which are of much higher value).