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Thanks Paolo for looking into this.
I installed the latest version 220.127.116.11 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.
Install the 18.104.22.168 when it will be approved by AMO and try to revert that preference to true, it should work as expected