Curl says bye bye to pipelining

HTTP/1.1 Pipelining is the protocol feature where the client sends off a second HTTP/1.1 request already before the answer to the previous request has arrived (completely) from the server. HTTP/1.1 Pipelining was badly supported by curl for a long time in the sense that we had a series of known bugs and it was a fragile feature without enough tests. The bad state of HTTP pipelining was a primary driving factor behind HTTP/2 and its multiplexing feature.

Source: daniel.haxx.se