In fact, "Containers on the Go" seems to do this: https://addons.mozilla.org/en-us/firefox/addon/containers-on-the-go/ https://addons.mozilla.org/en-us/firefox

In fact, "Containers on the Go" seems to do this: https://addons.mozilla.org/en-us/firefox/addon/containers-on-the-go/ https://addons.mozilla.org/en-us/firefox/addon/containers-on...