[akazantsev]

Really? Then you can claim that Chrome has supported "profiles" since its inception, with the `--user-data-dir` command-line switch. If something is not user-visible, it is as good as non-existent. Firefox has no profiles as far as a regular user is concerned.

[ReadCarlBarks]

The new profile manager has already been enabled for most users.

If you don't see it in the main menu yet, type `about:config` into the address bar and toggle `browser.profiles.enabled`.