Apart from signing into multiple accounts or isolating pages under the same domain, is there any advantage to using Firefox containers from a security standpoint or do you think that Total Cookie Protection is sufficient for most use cases / threat models?
One thing that is really handy for development is that you can set up any container to use a proxy server. I use that a lot to reduce the sheer amount of crap that would get sent to the proxy if it were enabled at the system level or in the regular browser network settings. It really keeps the noise down.