I just diffed the fingerprint[0] of 6 Mullvad browser sessions across 2 different devices and it was a unique fingerprint in every case[1]
It mixes a lot - fonts returned, media devices, the canvas ID - it's pretty good and similar to what you expect from the improvements out of Tor Browser
[0] using amiunique and fingerprint.js (now fingerprint.com) - which most of the nefarious ad networks use
[1] not that just as with Tor, you have to quit the browser or click the 'new identity' menu button. just closing a tab/window and re-opening is not enough. I've always believed that there could be a UI hint to this in private browsers with a unique color/background in the menubar as an indicator
It mixes a lot - fonts returned, media devices, the canvas ID - it's pretty good and similar to what you expect from the improvements out of Tor Browser
[0] using amiunique and fingerprint.js (now fingerprint.com) - which most of the nefarious ad networks use
[1] not that just as with Tor, you have to quit the browser or click the 'new identity' menu button. just closing a tab/window and re-opening is not enough. I've always believed that there could be a UI hint to this in private browsers with a unique color/background in the menubar as an indicator