/* Comfortable layout for Kindle content manager */
@namespace url(http://www.w3.org/1999/xhtml);

@-moz-document url-prefix("https://www.amazon.co.jp/mn/dcw/myx.html") {
  /* Add more height to "List of collection" box in "Add to collection" screen */
  .bulkAddToCollectionDialog_myx .myx-lgtbox-collection-vertical-scroll.recentCollection_myx {
    height: 30vh !important;
  }

  /* Enlarge the count of contents */
  .contentCount_myx {
    font: 1rem/2 sans-serif !important;
  }
  .contentCount_myx b {
    padding-right: 0.2em !important;
  }

  /* Avoid text wrap on table header */
  div[list-view-header-dmyx] .myx-column {
    white-space: nowrap !important;
    font-size: 12px !important;
  }
}

/* Comfortable layout for Kindle content manager */
@namespace url(http://www.w3.org/1999/xhtml);

@-moz-document url-prefix("https://www.amazon.co.jp/mn/dcw/myx.html") {
  /* Add more height to "List of collection" box in "Add to collection" screen */
  .bulkAddToCollectionDialog_myx .myx-lgtbox-collection-vertical-scroll.recentCollection_myx {
    height: 35vh !important;
  }

  /* Enlarge the count of contents */
  .contentCount_myx {
    font: 1rem/2 sans-serif !important;
  }
  .contentCount_myx b {
    padding-right: 0.2em !important;
  }

  /* Avoid text wrap on table header */
  div[list-view-header-dmyx] .myx-column {
    white-space: nowrap !important;
    font-size: 12px !important;
  }
}

Adjust the height to be able to show more candidates
Adjust the height to be able to show more candidates
