          # Don't set a fallback for the default language or any English variant
          # (as it's empty, so it'll ALWAYS fall back to the default language)
          if self.__language == settings.LANGUAGE_CODE or self.__language.startswith('en'):
              return
          default_translation = translation(settings.LANGUAGE_CODE)
          self.add_fallback(default_translation)
  
      def merge(self, other):
          """Merge another translation into this catalog."""
          if not getattr(other, '_catalog', None):
 
</s> remove     def _add_fallback(self):
 </s> add     def _add_fallback(self, localedirs=None): </s> remove     def __init__(self, language):
 </s> add     domain = 'django'

    def __init__(self, language, domain=None, localedirs=None): </s> remove         if self.__language == settings.LANGUAGE_CODE and self._catalog is None:
 </s> add         if (self.__language == settings.LANGUAGE_CODE and self.domain == 'django'
                and self._catalog is None): </s> remove         self._add_fallback()
 </s> add         self._add_fallback(localedirs) </s> remove     Returns a translation object.
 </s> add     Returns a translation object in the default 'django' domain.
        if self.domain == 'django':
            # Get from cache
            default_translation = translation(settings.LANGUAGE_CODE)
        else:
            default_translation = DjangoTranslation(
                settings.LANGUAGE_CODE, domain=self.domain, localedirs=localedirs
            )
          # Don't set a fallback for the default language or any English variant
          # (as it's empty, so it'll ALWAYS fall back to the default language)
          if self.__language == settings.LANGUAGE_CODE or self.__language.startswith('en'):
              return
        if self.domain == 'django':
            # Get from cache
            default_translation = translation(settings.LANGUAGE_CODE)
        else:
            default_translation = DjangoTranslation(
                settings.LANGUAGE_CODE, domain=self.domain, localedirs=localedirs
            )
          self.add_fallback(default_translation)
  
      def merge(self, other):
          """Merge another translation into this catalog."""
          if not getattr(other, '_catalog', None):
keep keep keep keep replace keep keep keep keep keep
 Reused the DjangoTranslation class for the javascript_catalog view

Thanks Tim Graham and Cristiano Coelho for the reviews.
Refs #26328, #26319. 
django/utils/translation/trans_real.py