About This HTML Issue
The id attribute of an HTML element, used to identify the element when linking, scripting or styling, must be unique in the whole document and must not contain whitespace.
Technically, in HTML5, 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 anidattribute should start with a letter.
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Last reviewed: September 02, 2024
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