📘 DOC: improve a11y (#806)

* Add `tabindex="0"` to `<pre>` so that they are navigable by keyboard users if they overflow.

* Landmark elements should have unique names https://dequeuniversity.com/rules/axe/4.3/landmark-unique

* Page must have one main landmark https://dequeuniversity.com/rules/axe/4.3/landmark-one-main

- Main landmark must not be contained by another landmark https://dequeuniversity.com/rules/axe/4.3/landmark-main-is-top-level

* Heading level cannot increase by more than one

* Ensure that links with the same accessible name serve a similar purpose

https://dequeuniversity.com/rules/axe/4.3/identical-links-same-purpose

* Just update the accessible name and require context for the visible link name

* Fix CSS from the removal of the second <main>

* Revert heading level change

1 files changed, 3 insertions, 0 deletions

diff --git a/docs/public/make-scrollable-code-focusable.js b/docs/public/make-scrollable-code-focusable.js
new file mode 100644
index 000000000..6fbf1eebe
--- /dev/null
+++ b/docs/public/make-scrollable-code-focusable.js
@@ -0,0 +1,3 @@
+Array.from(document.getElementsByTagName("pre")).forEach((element) => {
+  element.setAttribute("tabindex", "0");
+});