new warning message per Jungkee's suggestion

Author: ylafon

publish/service_worker_1/CR-service-workers-20191003/index.html

@@ -1499,7 +1499,7 @@ <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="cont
    <div data-fill-with="warning">
     <details class="annoying-warning" open>
      <summary>V1 Branch</summary>
-     <p>This spec is a subset of <a href="https://w3c.github.io/ServiceWorker/">the nightly version</a> that is advancing toward a W3C Recommendation. For implementers and developers who seek all the latest features, <a href="https://w3c.github.io/ServiceWorker/">Service Workers Nightly</a> is a right document that is constantly reflecting new requirements.</p>
+     <p>This spec is a subset of <a href="https://w3c.github.io/ServiceWorker/">the nightly version</a>. It is advancing toward a W3C Recommendation. For implementers and developers who seek all the latest features, <a href="https://w3c.github.io/ServiceWorker/">Service Workers Nightly</a> is the right document as it constantly reflects new requirements.</p>
     </details>
    </div>
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