Android Studio 2.2 Preview all screen sizes missing
<p>Android studio before 2.2 version at the xml design screen there was a view like  "Preview all screen sizes" (check the image) but I cannot find that in Android Studio 2.2 Beta 2.
<a href="https://i.stack.imgur.com/DkgzO.png"><img src="https://i.stack.imgur.com/DkgzO.png" alt="&quot;Preview all screen sizes&quot;"></a></p>

<p>My Android Studio version is: </p>

<blockquote>
  <p>Android Studio 2.2 Beta 2 <br>
  Build #AI-145.3200535, built on August 18, 2016<br>
  JRE: 1.8.0_76-release-b03 amd64<br>
  JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o<br></p>
</blockquote>

<p>Could you help me where is it, how can I open it? </p>