The headline is completely wrong, there was no bug fixed. The blinking cursor was an invention, not a bugfix.

> “The original Apple II did not support lowercase letters which is kind of surprising to most people,” Hertzfeld tells Inverse, laughing. “But the designer, Wozniak, made a trade-off that blinking characters were more important than lowercase letters.”

Herzfeld is mistaken: Wozniak himself says the lack of lowercase had a completely different reason:

  So, in the end, the basic reason for no lowercase on the Apple I and Apple II was my own lack of money. Zero checking. Zero savings.

https://www.vintagecomputing.com/index.php/archives/2833/why...

Utterly buries the lede. The actual content that explains where the blinking cursor comes from is ~1 paragraph.