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Author: HannaParsa

2-ui/99-ui-misc/01-mutation-observer/article.md

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 # Mutation observer
 
 `MutationObserver` is a built-in object that observes a DOM element and fires a callback when it detects a change.
 
 We'll first take a look at the syntax, and then explore a real-world use case, to see where such thing may be useful.
 
 ## Syntax
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 `MutationObserver` is easy to use.
 
 First, we create an observer with a callback-function: