I use Vivaldi as the main browser and this one from the beginning will not include APIs that compromise privacy, such as FLoC. Other Google APIs, which are in Chromium, are optional and can be disabled in the privacy settings. By far the largest number of extensions are in the Chrome Store, although it is not a problem to install extensions from other sources in Vivaldi. Many extensions, such as ad and tracker blocker, are inbuild as own functions, as well as other functions that make it unnecessary to use many extensions.
Firefox is certainly a valid alternative, with reasonable privacy, despite the fact that, like other browsers in the US, it is financed by surveillance advertising, that is, it sends user data to Alphabet inc, NEST and other Google advertising companies. And just like Chromium, it contains APIs from Google, which the user cannot easily deactivate. Not even Tor is secure against fingerprinting and surveillance.
The underlying problem is the very bad and even dangerous habit of the big oligopolies, mainly the United States, of putting the privacy of users at risk for commercial reasons and, until now, among many companies that are active against the practices of surveillance advertising. , Vivaldi is the only browser manufacturer, in the list there is no other in this campaign, not even Mozilla, which is very sad and leaves few options to the user, in view of having little to choose between Blink, Gecko and WebKit, apart of some unstable and compatible exotics. To choose, use a browser that lets the tracking used by web pages pass and / or track the user directly. Among those who do not, there are not many and none are from the United States.
This is reality, although I know that many will not like it.