x-ray: Crawling to another site on collection always undefined

This is the example from the documentation and works fine

  x('http://google.com', {
    main: 'title',
    image: x('#gbar a@href', 'title'), // follow link to google images
  }).write('google.json')

Now I tried with the dribble example but fetching info from another site

x('https://dribbble.com', 'li.group', [{
  title: '.dribbble-img strong',
  image: '.dribbble-img [data-src]@data-src',
  short_description: x('.dribbble-link@href', '.shot-desc p')
}])
  .paginate('.next_page@href')
  .limit(3)
  .write('results.json')

but I’m getting [ undefined,undefined,undefined] in the results.json file

executing DEBUG=x-ray node .

x-ray params: {"source":"https://dribbble.com","scope":"li.group","selector":[{"title":".dribbble-img strong","image":".dribbble-img [data-src]@data-src"}]} +0ms
  x-ray starting at: https://dribbble.com +4ms
  x-ray fetching https://dribbble.com +1ms
  x-ray got response for https://dribbble.com with status code: 200 +585ms
  x-ray params: [Circular] +139ms
  x-ray params: [Circular] +4ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767755-Prepare-And-Gather +0ms
  x-ray fetching https://dribbble.com/shots/2767755-Prepare-And-Gather +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767491-Framer-Code-Folds +1ms
  x-ray fetching https://dribbble.com/shots/2767491-Framer-Code-Folds +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767633-BK-Bridge-WIP +1ms
  x-ray fetching https://dribbble.com/shots/2767633-BK-Bridge-WIP +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767710-Tools +1ms
  x-ray fetching https://dribbble.com/shots/2767710-Tools +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767662-Need-for-Speed +0ms
  x-ray fetching https://dribbble.com/shots/2767662-Need-for-Speed +1ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767882-Cheers +0ms
  x-ray fetching https://dribbble.com/shots/2767882-Cheers +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768238-Happy-Birthday-Donald +1ms
  x-ray fetching https://dribbble.com/shots/2768238-Happy-Birthday-Donald +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +4ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767691-Tarot-Magician +1ms
  x-ray fetching https://dribbble.com/shots/2767691-Tarot-Magician +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +3ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768231-Smile-Season +0ms
  x-ray fetching https://dribbble.com/shots/2768231-Smile-Season +1ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767999-Outside-Lands-Patch-Tree +0ms
  x-ray fetching https://dribbble.com/shots/2767999-Outside-Lands-Patch-Tree +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767908-Hover-State-Animated +0ms
  x-ray fetching https://dribbble.com/shots/2767908-Hover-State-Animated +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +3ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768129-Beer-Mat-Pattern +1ms
  x-ray fetching https://dribbble.com/shots/2768129-Beer-Mat-Pattern +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray undefined is not a url. Skipping! +1ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray undefined is not a url. Skipping! +0ms
  x-ray paginate(".next_page@href") => "https://dribbble.com/shots?page=2" +2ms
  x-ray paginating "https://dribbble.com/shots?page=2" +1ms
  x-ray 2 page(s) left to crawl +0ms
  x-ray fetching https://dribbble.com/shots?page=2 +0ms
  x-ray got response for https://dribbble.com/shots/2767633-BK-Bridge-WIP with status code: 200 +558ms
  x-ray got response for https://dribbble.com/shots/2767882-Cheers with status code: 200 +47ms
  x-ray got response for https://dribbble.com/shots/2767491-Framer-Code-Folds with status code: 200 +21ms
  x-ray got response for https://dribbble.com/shots/2767755-Prepare-And-Gather with status code: 200 +32ms
  x-ray got response for https://dribbble.com/shots/2767710-Tools with status code: 200 +18ms
  x-ray got response for https://dribbble.com/shots/2767662-Need-for-Speed with status code: 200 +20ms
  x-ray got response for https://dribbble.com/shots/2768238-Happy-Birthday-Donald with status code: 200 +28ms
  x-ray got response for https://dribbble.com/shots/2768231-Smile-Season with status code: 200 +22ms
  x-ray got response for https://dribbble.com/shots/2767691-Tarot-Magician with status code: 200 +19ms
  x-ray got response for https://dribbble.com/shots/2767908-Hover-State-Animated with status code: 200 +25ms
  x-ray got response for https://dribbble.com/shots/2767999-Outside-Lands-Patch-Tree with status code: 200 +17ms
  x-ray got response for https://dribbble.com/shots?page=2 with status code: 200 +18ms
  x-ray params: [Circular] +27ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768045-DaBull-Final-Logo +0ms
  x-ray fetching https://dribbble.com/shots/2768045-DaBull-Final-Logo +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +0ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767907-Japanese-Games +0ms
  x-ray fetching https://dribbble.com/shots/2767907-Japanese-Games +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767716-Rift +0ms
  x-ray fetching https://dribbble.com/shots/2767716-Rift +2ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768246-Twitched-it-Viper-Shading-Texture-Process +1ms
  x-ray fetching https://dribbble.com/shots/2768246-Twitched-it-Viper-Shading-Texture-Process +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767669-OH-again +0ms
  x-ray fetching https://dribbble.com/shots/2767669-OH-again +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767734-Born-To-Lose +0ms
  x-ray fetching https://dribbble.com/shots/2767734-Born-To-Lose +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767595-Profile-screen-for-upcoming-ios-app +0ms
  x-ray fetching https://dribbble.com/shots/2767595-Profile-screen-for-upcoming-ios-app +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767743-WALL-E +0ms
  x-ray fetching https://dribbble.com/shots/2767743-WALL-E +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768567-Bulk-Edit-Mode-Interaction +1ms
  x-ray fetching https://dribbble.com/shots/2768567-Bulk-Edit-Mode-Interaction +1ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767651-House-On-Stilts +0ms
  x-ray fetching https://dribbble.com/shots/2767651-House-On-Stilts +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +0ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768218-Sad-Iron-Man +0ms
  x-ray fetching https://dribbble.com/shots/2768218-Sad-Iron-Man +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767552-Bridgestone-Icons +0ms
  x-ray fetching https://dribbble.com/shots/2767552-Bridgestone-Icons +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray undefined is not a url. Skipping! +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray undefined is not a url. Skipping! +0ms
  x-ray paginate(".next_page@href") => "https://dribbble.com/shots?page=3" +2ms
  x-ray paginating "https://dribbble.com/shots?page=3" +0ms
  x-ray 1 page(s) left to crawl +0ms
  x-ray fetching https://dribbble.com/shots?page=3 +0ms
  x-ray got response for https://dribbble.com/shots/2768129-Beer-Mat-Pattern with status code: 200 +198ms
  x-ray got response for https://dribbble.com/shots/2768045-DaBull-Final-Logo with status code: 200 +419ms
  x-ray got response for https://dribbble.com/shots/2767716-Rift with status code: 200 +25ms
  x-ray got response for https://dribbble.com/shots/2767669-OH-again with status code: 200 +20ms
  x-ray got response for https://dribbble.com/shots/2768246-Twitched-it-Viper-Shading-Texture-Process with status code: 200 +21ms
  x-ray got response for https://dribbble.com/shots/2767595-Profile-screen-for-upcoming-ios-app with status code: 200 +20ms
  x-ray got response for https://dribbble.com/shots/2767907-Japanese-Games with status code: 200 +18ms
  x-ray got response for https://dribbble.com/shots/2767743-WALL-E with status code: 200 +19ms
  x-ray got response for https://dribbble.com/shots/2767734-Born-To-Lose with status code: 200 +21ms
  x-ray got response for https://dribbble.com/shots/2767651-House-On-Stilts with status code: 200 +18ms
  x-ray got response for https://dribbble.com/shots/2768567-Bulk-Edit-Mode-Interaction with status code: 200 +19ms
  x-ray got response for https://dribbble.com/shots/2767552-Bridgestone-Icons with status code: 200 +15ms
  x-ray got response for https://dribbble.com/shots?page=3 with status code: 200 +72ms
  x-ray params: [Circular] +40ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768596-Self-Portrait +0ms
  x-ray fetching https://dribbble.com/shots/2768596-Self-Portrait +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768053-Firefly-Direction-3 +1ms
  x-ray fetching https://dribbble.com/shots/2768053-Firefly-Direction-3 +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767742-UEFA-EURO-2016-Poster-Series +1ms
  x-ray fetching https://dribbble.com/shots/2767742-UEFA-EURO-2016-Poster-Series +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767553-Dance-Party +0ms
  x-ray fetching https://dribbble.com/shots/2767553-Dance-Party +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768257-Umbrella-Alert +0ms
  x-ray fetching https://dribbble.com/shots/2768257-Umbrella-Alert +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768113-Hand +0ms
  x-ray fetching https://dribbble.com/shots/2768113-Hand +0ms
  x-ray params: [Circular] +1ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767959-Suns-out-guns-out +0ms
  x-ray fetching https://dribbble.com/shots/2767959-Suns-out-guns-out +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767496-Spaceboy-2 +0ms
  x-ray fetching https://dribbble.com/shots/2767496-Spaceboy-2 +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768325-Coastal-Oasis +1ms
  x-ray fetching https://dribbble.com/shots/2768325-Coastal-Oasis +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +2ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768317-2D-3D-mixed-illustration +0ms
  x-ray fetching https://dribbble.com/shots/2768317-2D-3D-mixed-illustration +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2768060-California-Dreamin +0ms
  x-ray fetching https://dribbble.com/shots/2768060-California-Dreamin +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray resolved ".dribbble-link@href" to a https://dribbble.com/shots/2767949-Dapper-Ink-Signage +0ms
  x-ray fetching https://dribbble.com/shots/2767949-Dapper-Ink-Signage +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +0ms
  x-ray resolving to a url: .dribbble-link@href +1ms
  x-ray undefined is not a url. Skipping! +0ms
  x-ray params: [Circular] +0ms
  x-ray params: [Circular] +1ms
  x-ray resolving to a url: .dribbble-link@href +0ms
  x-ray undefined is not a url. Skipping! +0ms
  x-ray reached limit, ending +1ms
  x-ray got response for https://dribbble.com/shots/2768218-Sad-Iron-Man with status code: 200 +162ms
  x-ray got response for https://dribbble.com/shots/2768596-Self-Portrait with status code: 200 +338ms
  x-ray got response for https://dribbble.com/shots/2767553-Dance-Party with status code: 200 +29ms
  x-ray got response for https://dribbble.com/shots/2767742-UEFA-EURO-2016-Poster-Series with status code: 200 +34ms
  x-ray got response for https://dribbble.com/shots/2768053-Firefly-Direction-3 with status code: 200 +34ms
  x-ray got response for https://dribbble.com/shots/2768113-Hand with status code: 200 +19ms
  x-ray got response for https://dribbble.com/shots/2768257-Umbrella-Alert with status code: 200 +15ms
  x-ray got response for https://dribbble.com/shots/2767959-Suns-out-guns-out with status code: 200 +16ms
  x-ray got response for https://dribbble.com/shots/2768325-Coastal-Oasis with status code: 200 +15ms
  x-ray got response for https://dribbble.com/shots/2767496-Spaceboy-2 with status code: 200 +13ms
  x-ray got response for https://dribbble.com/shots/2767949-Dapper-Ink-Signage with status code: 200 +14ms
  x-ray got response for https://dribbble.com/shots/2768317-2D-3D-mixed-illustration with status code: 200 +20ms
  x-ray got response for https://dribbble.com/shots/2768060-California-Dreamin with status code: 200 +55ms