I’m getting a client error “request header field too large” - it happens only on vercel on specific api. It works perfect on other environments. The specific api is /api/frontegg/[…frontegg-middleware]
Hey,
A 431 (Request Header Fields Too Large) error is an HTTP response status code that indicates the server is unwilling to process the request because the request headers are too large. This can happen due to several reasons:
- Extremely long cookie values
- Too many or excessively large HTTP headers
- Overly long user agent strings
- Large authentication tokens
Avoid setting large headers as it might cause 431 Request Header Fields Too Large error depending on your backend web server configuration.
See also: https://vercel.com/guides/how-to-bypass-vercel-body-size-limit-serverless-functions
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