A manual checklist is of course no substitute for automated testing, or static analysis, of your page. A checklist can though help us catch a certain class of issues that might not be surfaced by such tools, or that might result in false positives.
Most, if not all, of the "general" items can be identified with an automated testing tool or browser plugin, such as Axe by Deque. The component specific level checklists will require manual testing.
Ensure your page has a valid doctype e.g. <!doctype html> for HTML5