Every game book can use an update from time to time, especially ones like RPG books that have to cover basically all of existence. That's where Sage Advice comes in. It's Wizards of the Coasts' way to update their books. Head through and see some of the changes.
From the website:
Sage Advice is a series of articles in which Jeremy Crawford, one of the D&D Studio’s game design architects, talks about the design of the game’s rules and answers questions about them.
D&D books occasionally receive corrections and other updates to their rules and story. This Sage Advice installment presents updates to several books. I then answer a handful of rules questions, focusing on queries related to Fizban’s Treasury of Dragons and Strixhaven: A Curriculum of Chaos.