private static @NotNull @Unmodifiable Set<ArrangementSettingsToken> concat(@NotNull Set<? extends ArrangementSettingsToken> base,
                                                                             ArrangementSettingsToken... modifiers) {
    Set<ArrangementSettingsToken> result = new HashSet<>(base);
    Collections.addAll(result, modifiers);
    return Set.of(result.toArray(new ArrangementSettingsToken[0]));
  }
private static @NotNull @Unmodifiable Set<ArrangementSettingsToken> concat(@NotNull Set<? extends ArrangementSettingsToken> base,
                                                                             ArrangementSettingsToken... modifiers)