Missing Content-Lenght header (HTTP2Adapter on a HTTP 1/1 connection)

Package

http2_adapter

Version

2.6.0

Operating-System

Android

Adapter

Http2Adapter

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Dart Version

3.5.4

Steps to Reproduce

• perform a GET request using HTTP2Adapter on a HTTP 1/1 only backend
• repeat previous step many times (how many can vary: maybe 5, maybe 10) and maybe quickly - not sure exactly for the details
• trace the HTTP requests

Expected Result

all requests must have the Content-Length HTTP header (required on HTTP 1/1, optional only on HTTP 2/0)

Actual Result

Most of the requests do have the Content-Length header but some others don't

Start with the Http2Adapter request path and reproduce repeated GET requests against an HTTP/1.1-only backend while tracing the requests. Compare requests that include Content-Length with those that do not; done means every request sent over the HTTP/1.1 connection includes that header.