Update 3.3 release notes with rc6 updates since rc5

Change-Id: Iec53bae24415935961dd7a8e72425c4e1e0f7f15
diff --git a/pages/site/releases/3.3.md b/pages/site/releases/3.3.md
index dcbb9a2..633da4c 100644
--- a/pages/site/releases/3.3.md
+++ b/pages/site/releases/3.3.md
@@ -1,14 +1,14 @@
 ---
-title: "Gerrit 3.3.0-rc5 release (in development)"
+title: "Gerrit 3.3.0-rc6 release (in development)"
 permalink: 3.3.html
 hide_sidebar: true
 hide_navtoggle: true
 toc: true
 ---
 
-Download: **[3.3.0-rc5](https://gerrit-releases.storage.googleapis.com/gerrit-3.3.0-rc5.war)**
+Download: **[3.3.0-rc6](https://gerrit-releases.storage.googleapis.com/gerrit-3.3.0-rc6.war)**
 
-Documentation: **[3.3.0-rc5](https://gerrit-documentation.storage.googleapis.com/Documentation/3.3.0/index.html)**
+Documentation: **[3.3.0-rc6](https://gerrit-documentation.storage.googleapis.com/Documentation/3.3.0/index.html)**
 
 ## Release highlights
 
@@ -236,6 +236,9 @@
 
 ### UI issues
 
+* [Issue 7458](https://bugs.chromium.org/p/gerrit/issues/detail?id=7458);
+  Fix iron-dropdown positioning
+
 * [Issue 13080](https://bugs.chromium.org/p/gerrit/issues/detail?id=13080);
   Fix the position of the hovercard
 
@@ -248,6 +251,12 @@
 * [Issue 13433](https://bugs.chromium.org/p/gerrit/issues/detail?id=13433);
   Unlock scroll if hovercard detached
 
+* [Issue 13543](https://bugs.chromium.org/p/gerrit/issues/detail?id=13543);
+  Fix navigate back to change page with '[' on first diff.
+
+* [Issue 13658](https://bugs.chromium.org/p/gerrit/issues/detail?id=13658);
+  Convert comment counts to comment thread counts around the UI
+
 ## Documentation changes
 
 * config-reverseproxy.txt: Document X-Forwarded-For header