Issue description:
The existing content in the "ARIA role, state, and property allowances" cell for the Header element wrongly specify role=contentinfo instead of role=banner (as follows):
Roles: group, none or presentation. (If not a descendant of an article, aside, main, nav or section element, or an element with role=article, complementary, main, navigation or region, then role=contentinfo is also allowed, but NOT RECOMMENDED. Otherwise, role=generic is also allowed, but SHOULD NOT be used.)
I am submitting a pull request that resolve the issue.
I am submitting a pull request that resolve the issue.