* Under “Definitions,” “If DOCUMENT does not have a browsing context,
Let…” (should be “let”).

* Same section, “the stack of open elements is said be have” (seems to
miss “to”).

* Sometimes the word ”html” is used in lowercase, but not always
referring to the standard. It would be good to check for correct use
in the document, and to use capitals for references to the standard,
and a monospace font for references to the element.

* Inconsistent spelling of “insertion mode”. Headings, even for those
whose levels don’t use title case, seem to always say “Insertion
Mode,” while the copy following it says “insertion mode.” This seems
inconsistent either when it comes to the headings (as they’re not all
or completely using title case) or the copy (which should then also
refer to “Insertion Mode”).