@@ -246,7 +246,7 @@ class Preferences(object):
246246 def __init__(self, themes, categories, engines, plugins):
247247 super(Preferences, self).__init__()
248248
249− self.key_value_settings = {'categories': MultipleChoiceSetting(['general'], choices=categories),
249+ self.key_value_settings = {'categories': MultipleChoiceSetting(['general'], choices=categories + ['none']),
250250 'language': SearchLanguageSetting(settings['search']['language'],
251251 choices=LANGUAGE_CODES),
252252 'locale': EnumStringSetting(settings['ui']['default_locale'],