1. Win+R -> “firefox -p -no-remote” to open Firefox Profile Manager.

2. Press Create Profile.

3. Type a new profile name.

4. Finish, Exit.

5. Copy Firefox icon (Ctrl+C, Ctrl+V).

6. Open the new icon Properties.

7. In the Target field add this string to the end:

-p [your-created-profile-name] -no-remote

8. OK.