id

The id global attribute defines a unqiue identifier on an element.

Recommendation

It is highly recommended for an email client to support the id attribute.

The value of the id attribute on an element may be referenced in the values of other attributes on other elements such as the for and aria-labelledby attributes. Removing the id attribute in such cases affects the semantics of the HTML document and has negative impact on accessibility.

If a webmail client directly embeds HTML messages on the same webpage (see embedding contexts), then it is a good idea to prefix the values of id attributes within the HTML message to avoid clashes with values used by the email client elsewhere. However, all relevant references must also be prefixed such as:

• CSS selectors
• Values of attributes referencing the value of the id attribute (e.g. for, aria-labelledby)

Resources

• MDN: The id global attribute
• HTML Standard: The id global attribute

Email client compatibility

No compatibility data available.