diff --git a/desktop/org.kde.spectacle.appdata.xml b/desktop/org.kde.spectacle.appdata.xml
--- a/desktop/org.kde.spectacle.appdata.xml
+++ b/desktop/org.kde.spectacle.appdata.xml
@@ -326,6 +326,7 @@
   </description>
   <screenshots>
     <screenshot type="default">
+      <caption>Spectacle after taking a screenshot</caption>
       <image width="880" height="537">http://kde.org/images/screenshots/spectacle.png</image>
     </screenshot>
   </screenshots>