My favorite change is a fairly obscure tweak to Unicode Standard Annex #31, which defines guidelines and requirements for which codepoint sequences form valid identifiers (e.g. for programming languages)

The Bopomofo script (Zhùyīn fúhào) for phonetically representing Chinese was previously considered a "Recommended script" but has been recategorized as a "Limited use script" because it is generally used in educational contexts.