@ApiStatus.Experimental
  default void onCustomFoldRegionPropertiesChange(@NotNull CustomFoldRegion region,
                                                  @MagicConstant(flagsFromClass = ChangeFlags.class) int flags) {
  }
@ApiStatus.Experimental
  default void onCustomFoldRegionPropertiesChange(@NotNull CustomFoldRegion region,
                                                  @MagicConstant(flagsFromClass = ChangeFlags.class) int flags)