[jerheinze]

Thankfully Mozilla works with the Tor Project so that Tor Browser patches to Firefox get uplifted to mainline Firefox, you can read more about those efforts here: https://wiki.mozilla.org/Security/Tor_Uplift And the Tor Uplift tracker: https://torpat.ch/uplift

In this case the relevant preference is privacy.firstparty.isolate = true. Another worth pointing out pref is privacy.resistFingerprinting = true.

[milofeynman]

Thank you. I am excited for all the ways this is going to break the web for me, but this is exactly what I wanted. Maybe someday this will be on by default for everyone. Can you imagine?