> I don't understand why the default behavior isn't to isolate every website from every other website? There's an add-on that does something close to that: ht

> I don't understand why the default behavior isn't to isolate every website from every other website? There's an add-on that does something close to that: https://addons.mozilla.org/en-US/firefox/addon/temporary-containers/ https://addons.mozilla.org/en-US/firefox/addon/temporary-con... This add-on's options include opening each (sub)domain in its own container. These containers are temporary: they're deleted a short time after you close their last tab, so you have to log back into each site on each visit. (This may be something you do anyway.) I don't (yet?) know of an add-on that automatically assigns each domain you visit to its own permanent container, and automatically creates new containers for each new domain.