What can we learn from this? My knowledge falls short to understand all warnings and to take countermeasures.
Usually Firefox is te browser which confines the most with W3C best practices and advice. It seems that both Edge and Brave do a marginally better than Google. The practicality of these tests are marginal. The sandboxes and isolation policies are much more important together with update window (in which Chrome does a little better than Brave and Brave a little better than Edge) On linux and Windows the sandboxes of Chromium based browsers are a lot stronger than Firefox based browsers. On Windows users can even increase integrity level of untrusted to appcontainer. On top of that Chromium based browsers offer much more user management on site permissions. That said with so much security disadvantages of Firefox based browsers, there are still a lot of people who prefer Firefox for its better privacy settings.
When you favored Chromium based browsers, this thread probably won't change your opinion. When you preferred Firefox based browsers this thread will provide some ease of the pain of knowing you are using the browser with the weakest security.
