Case insensitive operations in `java.lang.String` class now correctly do case insensitive comparisons for supplementary characters (characters which have code point values over `U+FFFF`). For details, see the updates to the methods: ``` - compareToIgnoreCase(String other) - equalsIgnoreCase(String other) - regionMatches(boolean ignoreCase, ...) ``` For example, ``` "\ud801\udc00".equalsIgnoreCase("\ud801\udc28") ``` returns `true`, because '𐐀' ("\ud801\udc00") and '𐐨' ("\ud801\udc28") are equal to each other character in case insensitive comparison.