Browser maker concerns
Browser maker Vivaldi said yesterday: FLoC off! Vivaldi does not support FLoC. Co-founder and CEO Jon von Tetzchner added: Our privacy policy is simple and clear; we do not want to track you.
He added that FLoC would expose personal data in new ways. You might visit a website that relates to a highly personal subject that may or may not use FLoC ads, and now every other site that you visit gets told your FLoC ID, which shows that you have visited that specific kind of site, he said.
These risks could go beyond embarrassment to have serious implications for society if used by authoritarian governments. A dictatorship may be able to work out that dissenters often seem to have one of the same five FLoC IDs. Now anyone who visits a nationally controlled website with that ID could be at risk, he added. We will not support the FLoC API and plan to disable it, no matter how it is implemented.