- CircleCI
- GitHub
- JIRA (blecch, but I have to use it...)
- AWS
- Google Docs (for work, and the rare personal use of Google stuff can just happen in one of the general browsers I am using)
...and others.
The OS does a much better job of partitioning windows and groups of windows than a browser typically does. You can easily keep switch between groups of windows, or keep them in their own workspace/desktop, etc.
Plus you can keep your cookies and saved passwords isolated between the environments... the browser handling AWS doesn't need to store or have access to the pasword for my Google account, and so on. For production type apps you can disable saved passwords entirely.
It is incredibly useful, and the only thing I worry about is that on macOS (my main workstation OS) there is only one good solution for this I know of: Epichrome, which seems to be a one-man side project:
https://github.com/dmarmor/epichrome
Other solutions that I know of don't save passwords, or don't keep password/cookie stores separated between the browser instances.
(I think Chrome can do this by itself on other platforms.)