A POST without a body causes Membrane to wait on that thread.

RFC Reference (short)

• RFC 9112 (HTTP/1.1 Semantics) allows POST without body.
• A sender should send a Content-Length or Transfer-Encoding only if a body exists.
• Absence of either simply means: empty body.

Change:
If there is no Content-Length and no Transfer-Encoding => Do not wait but Forward

Cases:

POST /foo
Content-Type: application/json

=> Request with empty body => Forward

POST /
Content-Length: 5

hello

=> Forward