Multifox creates a button on Firefox toolbar. Select New. Now your logins in this tab are independent of other Firefox tabs.
For example, if you have multiple Gmail accounts, you can open them all at the same time. Each Firefox tab, managed by Multifox, accesses an account without interfering each other.
Each Multifox tab is flagged with a number indicating the identity profile. Logins made in tabs with different numbers are isolated.
Per-tab identities are a new feature introduced in Multifox 3. Identity Profiles used to be per-window.
If you need to access 12 Gmail accounts you will need 12 tabs with different identity profiles. You can have as many identities as you want.
Selecting a different identity profile from Multifox menu will modify the profile for current tab and reload the page.
The identity profile of each tab is preserved when Firefox restores the session, or reopen a tab.
Selecting a profile with a click will modify the profile for current tab and reload the page. To open the current page in a new tab, use a middle-click (or ctrl+click).
You can open links in new tabs using a specified Multifox profile. It works for bookmarks as well.
It is possible to rename identities profiles to something more meaningful than a number. Click Edit from Multifox menu, then select Rename Profile.