J.K. Rowling has been a notorious bitch, even before her "go woke or go broke" phase.
Enter:
The Harry Potter Lexicon
This was a fanmade site that listed all the spells, characters, places, you name it in the Potterverse because it was a fucking mess and no one had created an encyclopedia or anything at the time.
Rowling herself, if you look at the link, admits to having used the Lexicon to look up spells and information she forgot while writing her own damn books.
Then the lawsuit happend.
The Harry Potter Lexicon published their information and Rowling sued the pants off them in 2008, citing it was her stuff. Luckily, they won and but they had to redo their whole book and modify it (I think some minor publication laws came into it).
JK is still bitchy about it to this day from what I understand.