Is there not an existing more browser-specific appropriate place for this to go? I think you mentioned in the ticket that `dojo/_base/sniff` is not always loaded, but then I wonder what is. In any case, as mentioned in ticket #16663 comment 3, this does not fix the condition for dojo/i18n users that are not also using the dojo v1 amd loader. The actual fix for #16663 is to make sure that `targetLocale` is an empty string instead of `undefined`.