Add 21.12 release notes

org.kde.neochat.appdata.xml

@@ -188,6 +188,29 @@
     <content_attribute id="social-chat">intense</content_attribute>
   </content_rating>
   <releases>
+    <release version="21.12" date="2021-12-07">
+      <description>
+        <p>NeoChat 21.12 brings lots of new features and fixes</p>
+        <ul>
+          <li>Solved various problems related to login, logout and account switching</li>
+          <li>Fixed a few problems in the timeline layout</li>
+          <li>Added Spell checking while writing a message</li>
+          <li>Improved Settings pages</li>
+          <li>Many improvements to the android and general mobile support</li>
+          <li>Show blurhashes while images load</li>
+          <li>Support showing custom emojis</li>
+          <li>Added a global menu</li>
+          <li>Added support for spoilers</li>
+          <li>Added a quick switcher to switch between rooms</li>
+          <li>Added support for an optional fancy blur background effect</li>
+          <li>Resizable left and right drawers</li>
+          <li>Added Syntax highlighting in raw json messages</li>
+          <li>Better wayland support</li>
+          <li>Improved file reception and download</li>
+        </ul>
+      </description>
+      <url>https://www.plasma-mobile.org/2021/12/07/plasma-mobile-gear-21-12/</url>
+    </release>
     <release version="1.2.0" date="2021-06-01">
       <description>
         <p>NeoChat 1.2 brings a major redesign of the user interface. The chat page is now using bubbles for the messages and the input component was completely rewritten with a nicer look as well.</p>