I stubled upon https://browserleaks.com/javascript and tested brave and firefox (scripts ON).
As expected, both browsers leaked some info. However
Firefox DIDNT let anything show in the following categories, while brave gave it away:
- Battery Status API
(API Support, Battery is Charging, Battery Charging Time, Battery Discharging Time, Battery Level, Diagnosis) - Network Information API
(API Support, effectiveType, rtt, downlink, saveData)
According to this post https://github.com/brave/browser-laptop/wiki/Fingerprinting-Protection-Mode battery status shouldnt have leaked.
Brave Version 0.62.51, windows 10
-ads and trackers blocked
-connection encrypted
-3rd party cookies blocked
-all scripts allowed
-device recognition blocked
If tested with all scripts disabled, nothing leaks as expected.
I am just suprised firefox by default hides more javascript info than brave. Please look into it.