Firefox has done this for a very long time: its called profiles and you can read up on it at https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-

Firefox has done this for a very long time: its called profiles and you can read up on it at https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data https://support.mozilla.org/en-US/kb/profiles-where-firefox-.... You can simply run firefox.exe -p and pull up the profile manager (you have to make sure all instances of Firefox are closed first) and you can create as many profiles as you want. Once you have a profile (for example, "worktrello") you can launch it with firefox -P "worktrello" -no-remote and it will be a completely separate process, with its own cache and cookies and all.