Rated 5 out of 5 stars

Hi Paolo, it seems that the add-on stopped working in Firefox 21. Upon launching another profile, the message is "Unable to file executable".

This review is for a previous version of the add-on (1.5.0.2.1-signed). 

It's fixed in 1.5.0.3 version, you can find it here https://addons.mozilla.org/it/firefox/addon/profileswitcher/versions/