Google’s Topics API will not be enabled in Vivaldi, and it cannot work in Vivaldi. It would need two things to make it work, and we have disabled both of them.
It would need a setting enabled for it to collect local profiles about you. We disable the setting by default, and we forcibly do it in a way that means that changes to Chromium cannot remotely enable it. We do not provide any settings UI to allow you to change it, and we will soon remove the new Chromium settings section for it. (Technically, you could enable it by editing your settings or installing an extension that manipulates it. However, all that would do is enable local data collection. It will not be used because of #2)
Before exposing the Topics API information to websites, Chromium checks if the setting is enabled or disabled. We forcibly make it always return “disabled”, even if it is enabled. So that even if you somehow manage to bypass #1 and enable local profile collection, it will not expose it to Google or other websites.
The Vivaldi devs know Chromium at the millimeter and also all Google’s dirty tricks, as they have shown for more than 7 years, nipping all Google’s attempts to control Chromium in the bud. The point is that Google is now coming up with this new crap that wants to introduce this WEI DRM API on web pages and it’s services, which would affect ALL browsers, not just Chromium, by requiring a Google “security” token in browsers as a passport to be able to access these websites and services.