Then there shouldn't be an issue for you then @Teophrast . As @qwerzxcva already pointed out:

When you clear the cookies of a website and reopen it, it will change.

Since Cross-site tracking cookies are disabled by default different site visits will produce different canvas fingerprints. If you are interested in investigating this further @Teophrast and run some experiments it will be interesting for sure. Most of the testing sites I know work under the same domain which makes it hard to reproduce your scenario.

@FaFre The question is does two distinct websites with that level of protection can produce same fingerprint within one browser sesion or not. Which is hard to test, because testing websites have their own custom fingerprinting scripts unlike commercial ones. It cannot be entirelly cookie dependand, otherwise it would mean if we block cookies then fingerprinting will fail, which make no sense.

Also, i tested, and if you dont delete cookies, and you close and open browser your figerprint will change, and they will know that you are using antifingerprinting techniques. If you are staying logged in or you want to keep cookies to save your website settigs, like dark mode, it will make per session randomization not useful, unless you use browser with same logic like firefox focus. It is anonymity focused, not privacy focused.

Meanwhile, per figerprinting event randomization is straightforward and doesnt try to mimic normal user, it for sure keeps you safe from cross-website figerprinting, which is privacy focused way. Also, like switching on "do not track me" setting in browser, it reveals you.

It would be great if you can share the details how you tested it @Teophrast so I can reproduce it. Did you compare your results with IronFox and maybe also Bromite? Would be interesting to know how they behave in such scenarios.

@FaFre So i just enabled canvas randomization in fingerprint protecton settings, disabled my extensions, including one that delets cookies. And i opened test website. I closed the browser and opened it again. Fingerprint was different, even though cookies or cache wasnt removed. Which means if website owner can idnetify you trough other means, like cookies or login or behavior analisis he will find out that you are trying to mimic.

Also, same weblibre can be used in different ways trough profiles. For example if i set up profile that behaves like firefox focus - clear cache, delete cookied, remove history, etc, apon closing, then i would be very happy with stock fingerprint protection. But for daily use profile it dont make that much sense, because you identify yourself to website owner trough login or trough cookies anyway.

I dont have that much browsers installed, only fennec, which is almost vanilla firefox. I mostly tested browser fingerprint protection logic against "canvas blocker" extension, to see what is differences. Canvas blocker does per event randomization, so its basicslly makes fingerpinting scripts useless, as if you were blocking fingerprinting attempts entirelly, but websites dont break.

My research shows that brave uses per session randomization but just like canvas blocker it passes same script two domains test, because it randomizes per session+per domain. For other browsers i am not sure. But it is also more suspicious than per event rqndomization. Because if you are logged in, and website owner knows that your fingerprint changes daily, it can detect mimicing. In other words per event randomisation visible from beggining, thus less suspicious. In general no browser out of box does per event rwndomization, which makes fingerprint protection in browsers purelly anonymous mode setting, when you want to have clear sessions with no personal info attached.

@FaFre Also, what i realized after some reflexion on topic, diffefent optional policies on figerprinting is actually a very good thing. It can be part of a profile presets.

Like if you want work/official profile, you shouldnt have any fingerprint protection, for example if you visiting banking apps. Because thos can ban you or misbehave in a way. For anonymous profile you want very deep thought sophisticated fingerprint protrction, that can cover you in between sessions, so website owner dont recognize you as same person, and cant detect any fingerprint protection being used. And for daily use profile where you logged in into social apps, you want more agressive fingerprint protection, like one of extensions, per event, or no protection at all.

And also other components and hardening settings can be part of such presets, to make intuitive management of profiles, and actually push people to use them. Beause most of people will actually use different browsers for different purposes, but this days one browser can cover all purposes if have profiles and extensive tweaking ability. Most of the people just dont want to be bothered with settings. Which is another reason why browsers like ironfox dont become popular. People do use them, but only for specific purposes, while they do the rest of browsing in chrome or other popular browser.