[Markdown] [Web/HTML] Fix up remaining notes

[wbamberg]

Part of #8961.

This fixes up the remaining notes in the HTML docs. There might be a small follow-up: it'll be easier to see once the other note fixes are all merged.

Many notes here are about not using obsolete elements/attributes and I've often changed them to warnings. I think we ought to remove all documentation of obsolete HTML (and possibly keep it in a separate HTML/Obsolete, or just delete it).

[github-actions]

Preview URLs

• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Attributes/disabled
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Attributes/required
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Attributes
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/acronym
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/bgsound
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/big
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/caption
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/center
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/col
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/colgroup
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/dir
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/fieldset
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/font
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/iframe
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/input/image
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/input/radio
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/label
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/li
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/link
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/menu
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/meta/name
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/plaintext
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/q
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/s
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/strike
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/thead
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Element/tt
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Global_attributes/autofocus
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Global_attributes/itemprop
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Global_attributes/nonce
• https://pr9154.content.dev.mdn.mozit.cloud/en-US/docs/Web/HTML/Global_attributes/style

Flaws

Note! 24 documents with no flaws that don't need to be listed. 🎉

URL: /en-US/docs/Web/HTML/Element/link
Title: <link>: The External Resource Link element
on GitHub
Flaw count: 1

• broken_links:
  • Can't resolve /en-US/docs/Archive/Web_Standards/Correctly_Using_Titles_With_External_Stylesheets

---

URL: /en-US/docs/Web/HTML/Element/dir
Title: <dir>: The Directory element
on GitHub
Flaw count: 1

• macros:
  • /en-US/docs/Web/API/HTMLDirectoryElement does not exist

---

URL: /en-US/docs/Web/HTML/Element/input/radio
Title: <input type="radio">
on GitHub
Flaw count: 1

• sectioning:
  • 'value' is not a unique ID in this HTML (temporarily changed to value_2)

---

URL: /en-US/docs/Web/HTML/Element/meta/name
Title: Standard metadata names
on GitHub
Flaw count: 1

• broken_links:
  • Can't resolve /en-US/docs/Mobile/Viewport_meta_tag

---

URL: /en-US/docs/Web/HTML/Attributes
Title: HTML attribute reference
on GitHub
Flaw count: 48

• broken_links:
  • Can't resolve /en-US/docs/Web/HTML/Attributes/action
  • Can't resolve /en-US/docs/Web/HTML/Attributes/align
  • Can't resolve /en-US/docs/Web/HTML/Attributes/alt
  • Can't resolve /en-US/docs/Web/HTML/Attributes/autofocus
  • Can't resolve /en-US/docs/Web/HTML/Attributes/autoplay
  • and 43 more flaws omitted

---

URL: /en-US/docs/Web/HTML/Attributes/disabled
Title: disabled
on GitHub
Flaw count: 2

• broken_links:
  • Can't resolve /en-US/docs/Web/HTML/Attribute/autocomplete
• bad_bcd_queries:
  • No BCD data for query: html.elements.attributes.disabled

---

URL: /en-US/docs/Web/HTML/Attributes/required
Title: HTML attribute: required
on GitHub
Flaw count: 3

• macros:
  • /en-US/docs/Web/API/ValidityState/valueMissing does not exist
  • /en-US/docs/Web/CSS/validityState.valueMissing does not exist
• bad_bcd_queries:
  • No BCD data for query: html.elements.attributes.required

External URLs

URL: /en-US/docs/Web/HTML/Element/plaintext
Title: <plaintext>: The Plain Text element (Deprecated)
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/big
Title: <big>: The Bigger Text element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/link
Title: <link>: The External Resource Link element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/dir
Title: <dir>: The Directory element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/iframe
Title: <iframe>: The Inline Frame element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/strike
Title: <strike>
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/tt
Title: <tt>: The Teletype Text element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/center
Title: <center>: The Centered Text element
on GitHub

No external URLs

---

URL: /en-US/docs/Web/HTML/Element/menu
Title: <menu>
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/caption
Title: <caption>: The Table Caption element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/font
Title: <font>
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/s
Title: <s>
on GitHub

• https://adrianroselli.com/2017/12/tweaking-text-level-styles.html (1 time)
• https://developer.paciellogroup.com/blog/2017/12/short-note-on-making-your-mark-more-accessible/ (1 time)
• https://www.w3.org/TR/html-aria/ (1 time)

---

URL: /en-US/docs/Web/HTML/Element/input/image
Title: <input type="image">
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/input/radio
Title: <input type="radio">
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/q
Title: <q>: The Inline Quotation element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/thead
Title: <thead>: The Table Head element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/li
Title: <li>
on GitHub

• https://w3c.github.io/aria/ (10 times)

---

URL: /en-US/docs/Web/HTML/Element/colgroup
Title: <colgroup>
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/col
Title: <col>
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/acronym
Title: <acronym>
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/label
Title: <label>
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/meta/name
Title: Standard metadata names
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/bgsound
Title: <bgsound>: The Background Sound element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Element/fieldset
Title: <fieldset>: The Field Set element
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Attributes
Title: HTML attribute reference
on GitHub

• https://dom.spec.whatwg.org/ (1 time)
• https://html.spec.whatwg.org/dev/interaction.html (1 time)
• https://w3c.github.io/html-media-capture/ (1 time)
• https://www.w3.org/TR/html52/infrastructure.html (1 time)
• https://www.whatwg.org/specs/web-apps/current-work/multipage/urls.html (2 times)

---

URL: /en-US/docs/Web/HTML/Attributes/disabled
Title: disabled
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Attributes/required
Title: HTML attribute: required
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Global_attributes/nonce
Title: nonce
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Global_attributes/autofocus
Title: autofocus
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Global_attributes/style
Title: style
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/HTML/Global_attributes/itemprop
Title: itemprop
on GitHub

No new external URLs