For anyone not familiar with the concept:
Browser profiles aim to separate the clean browser installation from whatever user-chosen additional action. Profiles are parallel folders within the hidden browser installation folder. You can simply switch between them. Your (literary named) default profile folder is not affected. You can even start your fresh 'test' profile to test X-notifier, add all your regular stuff and decide to ditch (delete) your previous default profile in order to rename the 'test' profile to 'default'.