The Multi-Account Containers extension is great for this. Each container keeps its own context, so you can be logged in to the same service twice (or more) in tabs in one window. Can set it up so that some sites will always use a certain container, or that sites in a container will always use a proxy. That is EXTREMELY useful to me.
https://addons.mozilla.org/en-US/firefox/addon/multi-account-containers/
Yeah, you’re right. I guess we may as well just give up and give in to the inevitable.