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CORS: Access-Control-Allow-Origin cannot be '*' when Access-Control-Allow-Credentials is 'true'

Access to fetch at 'https://api.example.com/me' from origin 'https://app.example.com' has been blocked by CORS policy: The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'.
Immediate Remediation
typescript
Set Access-Control-Allow-Origin to the explicit request origin (e.g. req.headers.origin) instead of wildcard * when credentials: include is used.
Root Cause Analysis

Encountered in CORS / Fetch when standard runtime constraints or configuration contracts are breached.

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