That's probably Firefox's own Firefox Multi-Account Containers[0]. Groups caches/cookies into designated categories for each tab (personal, work, shopping, etc.), with smart recognition for assigned sites.
Someone should do a study on the performance impacts of using something like this on all sites for various kinds of "typical" web browsing profiles. I'm honestly guessing a lot of the losses would be in the noise for me personally.
I've had first party isolation turned on for possibly a couple of years now (certainly since before the pandemic) and it does break a small number of sites but nothing I particularly care about. Except that one internal tool that I've taken to loading in Chrome :P.
I don't recall the last time I had to temporarily disable it to allow something to work.
I believe the 'First-party isolation' feature does this, but you need to enable it from about:config, and even then, I'm not sure if it is complete or bug-free.
I'd like to see something like the firefox container extension automatically open a new container for every unique domain name. It could get tricky for eg. federated logins, so I'm not 100% sure what the implementation would look like. But it'd be nice to have the option.
The Temporary Containers addon[1] does this. Combined with the usual Multi-Account Containers "always open this site in..." mechanism you can have some sites always open in a single container, but all other sites open in temporary containers that get deleted shortly after you close their tab.
jrmann100|5 years ago
[0] https://addons.mozilla.org/en-US/firefox/addon/multi-account...
nixpulvis|5 years ago
andrewaylett|5 years ago
I don't recall the last time I had to temporarily disable it to allow something to work.
cassianoleal|5 years ago
I use it to automatically open every new tab in its own temporary container.
[0] https://addons.mozilla.org/en-US/firefox/addon/temporary-con...
Santosh83|5 years ago
ajvs|5 years ago
jniedrauer|5 years ago
SAI_Peregrinus|5 years ago
[1] https://addons.mozilla.org/en-US/firefox/addon/temporary-con...
cmeacham98|5 years ago