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MutationObserver

Technical Definition & OverviewUpdated 2026-05-26
MutationObserver
A built-in Web API that provides the ability to watch for changes being made to the DOM tree.

Detailed Explanation

The MutationObserver interface provides the ability to watch for changes being made to the DOM tree. It is designed as a replacement for the older Mutation Events feature, part of the DOM3 Events specification. It provides a way to asynchronously observe changes to elements, attributes, and text nodes.

How Relyv helps: Relyv uses a highly optimized MutationObserver wrapper that includes "DoS protection" to prevent performance degradation during massive DOM churn.

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