The container functionality is built-in since it's a pretty pervasive mechanism, but yes, there is no default UI for it currently shipped. There are other inter

The container functionality is built-in since it's a pretty pervasive mechanism, but yes, there is no default UI for it currently shipped. There are other interfaces to it besides Multi-account Containers, such as Temporary Containers[1][2], Facebook Container[3] and Google Container[4]. [1]: https://addons.mozilla.org/en-US/firefox/addon/temporary-containers/ https://addons.mozilla.org/en-US/firefox/addon/temporary-con... [2]: https://github.com/stoically/temporary-containers https://github.com/stoically/temporary-containers [3]: https://addons.mozilla.org/en-US/firefox/addon/facebook-container/ https://addons.mozilla.org/en-US/firefox/addon/facebook-cont... [4]: https://addons.mozilla.org/en-US/firefox/addon/google-container/ https://addons.mozilla.org/en-US/firefox/addon/google-contai...