about:tor semantic and accessibility problems

Some issues with the about:tor page:

1. I'm not sure "About Tor" is the best document title. Wouldn't it be "About Tor Browser", or "Tor Browser Ready" or "Tor Browser Home"?
2. The "New to Tor Browser" button (#onboarding-overlay-button) has an almost invisible "focus-visible" styling. And the color contrast is poor.
3. The search input (#search-text) has no "focus-visible" styling.
4. The search button (#search-button) has "focus-visible" outline that isn't consistent with the rest of the page: it has thin dotted outline, whilst the links have a thick blue outline.
5. The search label (#searchlabel) has no text content (it is just a background image) so does not work as a label for the search input.
6. All the <img> elements (#onboarding-overlay-button-icon, #torcontent-logo, #bannerImg, and #imageStyle) do not have an alt="" attribute.
7. A lot of the link text ends in the "»" symbol. I'm not sure why we do this, but it does not read well on a screen reader. So it should be removed or visual only.
8. I feel like the .heading1 text is meant to act as the page's heading, so should be a <h1>.
9. The page uses lots of <div>s instead of elements with more structural semantics.