code: @NotNull
    public static byte[] serializePointer(@NotNull Map<String, String> pointer) {
      final Map<String, String> data = new TreeMap<>(pointer);
      final StringBuilder buffer = new StringBuilder();
      // Write version.
      {
        String version = data.remove(VERSION);
        if (version == null) {
          version = VERSION_URL;
        }
        buffer.append(VERSION).append(' ').append(version).append('\n');
      }
      for (Map.Entry<String, String> entry : data.entrySet()) {
        buffer.append(entry.getKey()).append(' ').append(entry.getValue()).append('\n');
      }
      return buffer.toString().getBytes(StandardCharsets.UTF_8);
    }
docs: Serialize pointer map.
  
  @param pointer Pointer data.
  @return Pointer content bytes.