Added summary 📝

recipe/0229-behavior-ranges/index.md

@@ -3,7 +3,7 @@ title: Adding Thumbnail Navigation and no-nav to a Video Resource
 id: 229
 layout: recipe
 tags: structure
-summary: "tbc"
+summary: "How to tell a viewer to create a thumbnail-based visual navigation of a video as well as to exclude a segment of that video from any such navigation."
 viewers:
 topic: 
  - structure