MDN URL

https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/id

What specific section or headline is this issue about?

#sect2

What information was incorrect, unhelpful, or incomplete?

This bold phrase: "should start with a letter" here:

Note: Technically, the value for an id attribute may contain any character, except whitespace characters. However, to avoid inadvertent errors, only ASCII letters, digits, '_', and '-' should be used and the value for an id attribute should start with a letter.

contradicts the HTML5 spec which says:

There are no other restrictions on what form an ID can take; in particular, IDs can consist of just digits, start with a digit, start with an underscore, consist of just punctuation, etc.

What did you expect to see?

The blue note agreeing with the HTML5 spec, i.e. stating that an ID could start with a letter.

Do you have any supporting links, references, or citations?

No response

Do you have anything more you want to share?

No response

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