         #     atEndEdge: atEndEdge
 
         if referenceFrame.page && 0 > pages.indexOf referenceFrame.page
-          console.warn "PagingScrollElement#pages setter: New page list does not contain the current referenceFrame. ALWAYS include the current referenceFrame when setting pages. Screen will jump!"
+          console.warn(
+            """
+            PagingScrollElement#pages setter: New page list does not contain the current referenceFrame. ALWAYS include the current referenceFrame when setting pages. Screen will jump!
+
+            page keys: #{inspect (page.key for page in pages)}
+            """
+          )
 
         if referenceFrame.page != page || referenceFrame.atEndEdge != atEndEdge
           # setReferenceFrame will call _updatePagesSplit

        totalSize += @getMainCoordinate page.getCurrentSize()
        break if totalSize >= pixelsOnScreen

      if totalSize < pixelsOnScreen
        averagePageSize = totalSize / pages.length
        pixelsLeft = pixelsOnScreen - totalSize
        count += ceil pixelsLeft / averagePageSize

        totalSize += @getMainCoordinate page.getCurrentSize()
        break if totalSize >= pixelsOnScreen

      if totalSize < pixelsOnScreen && pages.length > 0 && totalSize > 0
        averagePageSize = totalSize / pages.length
        pixelsLeft = pixelsOnScreen - totalSize
        count += ceil pixelsLeft / averagePageSize
