In the HTML, change the hyperlink for 21.5 to "#SupportLevels".
21.3.1, 1st paragraph
Replace the word "which" with the word "that".
21.4.1, 4th paragraph, first sentence
Replace the first sentence with the following text:
“shiftKey, controlKey, and altKey events are generated as each of the shift, control, and alt keys on the keyboard is respectively pressed and released.”
In the HTML, change the bookmark for 21.5 to "SupportLevels".