static Map<TextImageAction, File> filesForNiceButtons_map = weakIdentityHashMap();

static L<TextImageAction> filesForNiceButtons(L<File> l) {
  ret mapAndRecordToMap_reversed(filesForNiceButtons_map, l, func(final File f) -> TextImageAction {
    TextImageAction(f.getName(), isImageFile(f) ? #1101250 : #1101231, r-thread { genericUI_openFile(f) })
  });
}