Previously, the inclusion of the Accept-Language header in API requests was considered optional, and our systems would typically default to a standard localization. However, with the changes introduced in v4.39, omitting this header could lead to your application receiving data that is inconsistent with expectations.
To ensure the accuracy and consistency of the API responses you receive, we now strongly recommend that all API calls include an Accept-Language header.
Thank you,
Inca Lin
Fitbit Web API Support
Fitbit Developers oversee the SDK and API forums. We're here to answer questions about Fitbit developer tools, assist with projects, and make sure your voice is heard by the development team.
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