Rated 3 out of 5 stars

Thanks Paolo for looking into this.
I installed the latest version 1.7.5.1 but it still didn't fix the problem.
I then went to about:config and changed the property of "extensions.profileswitcher.use_onbeforeunload" to false in all the profiles I have created and I can finally switch between them again.

This review is for a previous version of the add-on (1.7.5.1-signed).  This user has a previous review of this add-on.

Install the 1.7.6.1 when it will be approved by AMO and try to revert that preference to true, it should work as expected