Chrome distrusted Symantec certs when 70 got pushed to stable (at the end of October)[1]. Digg shows NET::ERR_CERT_SYMANTEC_LEGACY error when I navigate to it. Firefox was supposed to remove the Symantec certs in 63 (also to be released at the end of October) but I guess they pushed it back a version[2].
All major browser coordinated to distrust the certs at the same time.
Although the rendering may still be done in kernel mode the parsing is now done in a usermode sandbox[1] which significantly reduces risks from handling untrusted fonts.
uBlock Origin + Google's Safe Browsing (or SmartScreen if you're an Edge user) should be enough for just about anyone. Furthermore one of the strengths of uBO is the ability to use dynamic filtering[1] which bypasses the filter list problem entirely.
If you're using uBlock Origin or uMatrix to block third party scripts it won't matter. That's what makes using the dynamic filtering in uBlock Origin so powerful. Easily the best bang for your buck ad blocking that you can do.
All major browser coordinated to distrust the certs at the same time.
[1] https://security.googleblog.com/2017/09/chromes-plan-to-dist...
[2] https://blog.mozilla.org/security/2018/07/30/update-on-the-d...