Issue with "@property": Where does the multiple property syntax come from?

[LeaVerou]

MDN URL: https://developer.mozilla.org/en-US/docs/Web/CSS/@property

The MDN article mentions a multiple property syntax:

@property --primary-color,
@property --secondary-color,
@property --text-color {
  syntax: '<color>';
  inherits: true;
}

@property --primary-color {
  initial-value: red;
}

@property --secondary-color {
  initial-value: blue;
}

@property --text-color {
  initial-value: green;
}

However, the grammar in the spec does not appear to support such a thing, nor is it supported by any implementation.

MDN Content page report details

• Folder: en-us/web/css/@property
• MDN URL: https://developer.mozilla.org/en-US/docs/Web/CSS/@property
• GitHub URL: https://github.com/mdn/content/blob/main/files/en-us/web/css/@property/index.html
• Last commit: 4c02f1d
• Document last modified: 2021-05-26T12:38:08.000Z

[rachelandrew]

Hmm... not sure but this web.dev article uses the same https://web.dev/at-property/

Which seems to have got into both places here: GoogleChrome/web.dev#4260

[rachelandrew]

I'll see if Una knows, because I don't understand this either.

[LeaVerou]

I wonder if @tabatkins knows.

[rachelandrew]

looks like it was an error GoogleChrome/web.dev#4433 (comment)

I'll update MDN

[rachelandrew]

that should be sorted once #5832 is merged, thanks for spotting this @LeaVerou