[JaRail]

I use Temporary Containers (https://addons.mozilla.org/en-US/firefox/addon/temporary-con...) to do this. You can customize how you want links handled when they target different domains. It takes some getting used to as there are a handful of options to understand/customize. Plus you can have customizations where you're replacing the current container with a new one which kills off your back button history. Just need to be aware of the quirks. It's definitely still in the realm of power-user UX.