A lot of times, Javascript is used to make dynamic content updates, without reloading a webpage. To make page changes announce to a screen reader, it helps to add the aria-live attribute to the element that will update. The two values you can add to the attrbute are polite and assertive:
aria-live="polite"Polite will announce updates once other actions are complete.
aria-live="assertive"Assertive will announce immediately
Often, update messages are added to a text element like a paragraph, but can be used to update whole sections of content (like the a group of headings and paragraphs elements inside a div)
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