Note that in this case, very specifically, they had to yank Firefox's javascript engine out of Firefox "but without the browser’s process sandbox and other defense-in-depth mitigations.” They had to remove the mechanisms designed to quash vulnerabilities. And they had to test explicitly against Firefox 147 vintage because Firefox 148 had already fixed the two issues that Mythos exploited to get an impressive number. Before Mythos even ran the key problems had been found and patched...