You probably use a secondary browser to login to
work and
personal accounts at the same time or check stuff with/ without add-ons, etc. If you love Firefox, you don't really have to put up with Chrome or Edge for this purpose.
You can use Firefox Developer Edition[1] as your secondary browser (while using Firefox at the same time).
Note - If you need a third or even a fourth browser, there is Firefox Beta and Firefox Nightly https://www.mozilla.org/en-US/firefox/channel/desktop/
[1] <https://www.mozilla.org/en-US/firefox/developer/>
