Unique IDs (IDs)
Axe-core deprecated + obsolete
Each element with an id attribute (e.g., <button id="submit">) has a unique id throughout the document - unless the id is an empty value.
Same id used twice:
These paragraphs have the same IDs:
If documentGetElementById("lol") is ever used, an error will be thrown automatically
This paragraph has id = "lol"
This paragraph has id = "lol"
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