Safari defaults to a poor choice of start page that leaks information to multiple third parties and allows them to set cookies without any user consent. Firefox also maintains an open websocket for push notifications that is linked to a unique identifier and so potentially can also be used for tracking and which cannot be easily disabled. Telemetry can be disabled, but again is silently enabled by default.

In addition, Firefox includes identifiers in its telemetry transmissions that can potentially be used to link these over time. For all three this happens via the search autocomplete feature, which sends web addresses to backend servers in realtime as they are typed. Chrome, Firefox and Safari all share details of web pages visited with backend servers. Start the browser from a fresh install/new user profile, type a URL and monitor traffic.įor Brave with its default settings we did not find any use of identifiers allowing tracking of IP address over time, and no sharing of the details of web pages visited with backend servers.Start the browser from a fresh install/new user profile and monitor network activity for 24 hours.Close the browser and restart, record network activity.Paste a URL into the address bar, press Enter, and record the user activity.Start the browser from a fresh install/new user profile.The test design was repeated multiple times for each browser. To inspect encrypted data, mitmdump was used and since leftovers can be an issue, extra care was used to delete all traces of previous installations from the systems. Chrome connections using QUIC/UDP had to be blocked so that the browser would fall back to TCP. The researcher logged all network connectivity on the devices the browsers ran on. Both also appear to send web page information to servers that 'appear unrelated to search autocomplete'. Edge sends the hardware UUID to Microsoft, and Yandex transmits a 'hash of the hardware serial number and Mac address'. Both send identifiers linked to the device hardware which means that the identifier persists even across installations.

The study found the Chromium-based Microsoft Edge web browser and Yandex to do worse than the other browsers of the test.

Privacy browser brave