message: Let the item get squashed if undefined
diff: @@ -103,15 +103,7 @@ const paginationWithPageAndPer: FieldMergeFunction<any, any> = (
  if (isInIncomingWindow) {
  const incomingItem = incoming[i - incomingStartingIndex]
  -
  - // are.na sometimes doesn't return the amount of items
  - // from the per argument. Set to null instead of undefined so that
  - // the undefined item doesn't get squashed.
  - if (incomingItem === undefined) {
  - newData[i] = null
  - } else {
  newData[i] = incomingItem
  - }
  } else if (Array.isArray(existing) && i < existing.length) {
  newData[i] = existing[i]
  } else {
  