val call3 = client.newCall(Request(server.url("/")))
    call3.execute().use { response ->
      assertThat(
        response.body.string(),
      ).isEqualTo("c")
    }

    // All calls share a connection.
    assertThat(server.takeRequest().sequenceNumber).isEqualTo(0)
    assertThat(server.takeRequest().sequenceNumber).isEqualTo(1)
    assertThat(server.takeRequest().sequenceNumber).isEqualTo(2)
  }