The command -no-remote -P « profile name » loads the Firefox profile « profile name » in a new instance making the browser window that opens independent from other open instances of Firefox.
On Windows, you have to modify shortcuts for that.
Right-click on the Firefox shortcut on the desktop and select Properties.
Locate the target field under shortcut and add the information to the end of the line (make sure there is a space-character between the end of the path and the command.
Example: « C:\Program Files (x86)\Firefox Developer Edition\firefox.exe » -P « testprofile -no-remote
The example loads the Firefox profile testprofile in a new instance.
Firefox Nightly is the cutting edge version of the browser. It is possible that the new profile selector will receive updates and improvements before it is made available in release versions of the web browser.
The main issue that I have with it right now is that it takes more time to load another profile using the new interface.
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