noembed element

<noembed> was meant to sit next to an <embed> and hold what to show instead when the embedded content couldn’t play: a link, a picture, a sentence explaining what was missing. It still turns up beside old media and plug-in embeds.

Why avoid

It is obsolete. The HTML Standard lists noembed among the elements that “are entirely obsolete, and must not be used by authors”, with the instruction: “Use object instead of embed when fallback is necessary.”

More to the point, nobody ever sees what’s inside it. The rendering section hides it outright, alongside script, style and template: noembed { display: none; }. There is no condition attached, so it stays hidden whether the embed next to it works or not. Its content isn’t even markup: the parser reads it with “the generic raw text element parsing algorithm”, so a link written inside is just text.

The embed it was paired with has no fallback either: “The embed element has no fallback content; its descendants are ignored.” When it fails, the reader gets nothing, and the fallback the author wrote, often the only accessible alternative to the embedded content, never reaches them.

Use instead

Use object, which has real fallback content: “The object element represents the element’s children. This is the element’s fallback content.” Whatever you put between its tags is shown when the resource can’t be:

<object data="chart.svg" type="image/svg+xml" width="600" height="400">
  <p><a href="chart.png">View the chart as an image</a></p>
</object>

Detectability

Fully detectable by tag name. deadhead never lints the content of a noembed, because a browser reads it as text. There is no autofix. Deleting the element would change nothing on screen, since it’s hidden, but it would also delete the fallback text you still need to move into an object.

Resources

• HTML Standard — Non-conforming features — noembed is obsolete; use object when fallback is necessary.
• HTML Standard — Rendering: hidden elements — noembed { display: none; }, unconditionally.
• HTML Standard — The embed element — embed has no fallback content.
• HTML Standard — The object element — an object’s children are its fallback content.
• MDN — <noembed> — obsolete and non-standard; use object with fallback content between its tags.