I actually love how multiple profiles are implemented in Firefox.
I have a keybinding on my system to launch "firefox -P" so that I can pick which profile to launch an instance of right away. I juggle between 5 different profiles at any time and it works exactly as I'd like it to. Additionally, it is much easier to do than setting up a complex multi-account container setup.
I have tabs for administrative work accounts and personal work accounts, along with restricting anything from Facebook into it's own container[2].
[0]: https://addons.mozilla.org/en-GB/firefox/addon/multi-account... [1]: https://support.mozilla.org/en-US/kb/containers [2]: https://addons.mozilla.org/en-GB/firefox/addon/facebook-cont...