BREAKING CHANGE: Fallbacks
Please check your Rails app for this line:
config.i18n.fallbacks = true
This setting is now incorrect as of this version of I18n. It should instead be:
config.i18n.fallbacks = [I18n.default_locale]
If not, fallbacks will be broken in your app by I18n 1.1.x.
Ensure that you are using config.i18n.fallbacks = [I18n.default_locale]
if you intend on fallbacks behaving correctly in I18n.