Node Mutation Hook Library

A small wrapper around MutationObserver to hook into creation of elements (filtered on CSS selector) or removal of nodes.

Verze ze dne 16. 02. 2026. Zobrazit nejnovější verzi.

Tento skript by neměl být instalován přímo. Jedná se o knihovnu, kterou by měly jiné skripty využívat pomocí meta příkazu // @require https://update.greasyfork.org/scripts/565361/1755404/Node%20Mutation%20Hook%20Library.js

Zeptejte se na otázku, přidejte recenzi nebo skript nahlašte.

Wrap lines

// ==UserScript==
// @name        Node Mutation Hook Library
// @namespace   https://greasyfork.org/users/1545341
// @version     2.1.0
// @license     MIT
// @author      abcenjoyer
// @description A small wrapper around MutationObserver to hook into creation of elements (filtered on CSS selector) or removal of nodes.
// ==/UserScript==

function hookCreation(selector, callback) {
  const observer = new MutationObserver((mutations) => {
    for (const record of mutations) {
      for (const node of record.addedNodes) {
        if (node.nodeType === Node.ELEMENT_NODE) {
          if (node.matches(selector)) {
            callback(node, observer);
          }

          for (const element of node.querySelectorAll(selector)) {
            callback(element, observer);
          }
        }
      }
    }
  });

  observer.observe(document.documentElement, {
    childList: true,
    subtree: true
  });
}

function hookRemoval(targetNode, callback) {
  const observer = new MutationObserver((mutations) => {
    for (const record of mutations) {
      for (const node of record.removedNodes) {
          if (node.contains(targetNode)) {
            observer.disconnect();
            callback();
          }
      }
    }
  });

  // observing the entire document is required because if targetNode is deleted because an ancestor node was, observing the parent won't work
  observer.observe(document, {
    childList: true,
    subtree: true
  });
}