TTP/1.1</code> to <code>HTTP/2</code> using the <code>Upgrade: h2c</code> header (<a href=https://github.com/istio/istio/issues/16391>Issue 16391</a>).</li></ul></div><nav class=pagenav><div class=left><a title="Istio 1.1.15 patch release." href=/v1.13/news/releases/1.1.x/announcing-1.1.15/ class=next-link><svg class="icon left-arrow"><use xlink:href="/v1.13/img/icons.svg#left-arrow"/></svg>1.1.15</a></div><div class=right><a title="Istio 1.1.13 patch release." href=/v1.13/news/releases/1.1.x/announcing-1.1