GFork

UserUtils

Library with various utilities for userscripts - register listeners for when CSS selectors exist, intercept events, modify the DOM more easily and more.
Contains builtin TypeScript declarations. Webpack compatible and supports ESM and CJS.
If you like using this library, please consider supporting the development ❤️

Full documentation on GitHub

Installation:

• If you are using a bundler like webpack, you can install this package using npm:

  npm i @sv443-network/userutils
  

  
  

  Then, import it in your script as usual:

  import { addGlobalStyle } from "@sv443-network/userutils";
  // or
  import * as userUtils from "@sv443-network/userutils";
  

  
  

  Shameless plug: I also have a webpack-based template for userscripts in TypeScript that you can use to get started quickly.

• If you are not using a bundler, you can include the latest release from GreasyFork by adding this directive to the userscript header:

  // @require https://greasyfork.org.cn/scripts/472956-userutils/code/UserUtils.js
  

  Then, access the functions on the global variable UserUtils:

  UserUtils.addGlobalStyle("body { background-color: red; }");
  

Features:

• DOM:
  • onSelector() - call a listener once a selector is found in the DOM
  • initOnSelector() - needs to be called once to be able to use onSelector()
  • getSelectorMap() - returns all currently registered selectors, listeners and options
  • getUnsafeWindow() - get the unsafeWindow object or fall back to the regular window object
  • insertAfter() - insert an element as a sibling after another element
  • addParent() - add a parent element around another element
  • addGlobalStyle() - add a global style to the page
  • preloadImages() - preload images into the browser cache for faster loading later on
  • openInNewTab() - open a link in a new tab
  • interceptEvent() - conditionally intercepts events registered by addEventListener() on any given EventTarget object
  • interceptWindowEvent() - conditionally intercepts events registered by addEventListener() on the window object
  • amplifyMedia() - amplify an audio or video element's volume past the maximum of 100%
• Math:
  • clamp() - constrain a number between a min and max value
  • mapRange() - map a number from one range to the same spot in another range
  • randRange() - generate a random number between a min and max boundary
• Misc:
  • autoPlural() - automatically pluralize a string
  • pauseFor() - pause the execution of a function for a given amount of time
  • debounce() - call a function only once, after a given amount of time
  • fetchAdvanced() - wrapper around the fetch API with a timeout option
• Arrays:
  • randomItem() - returns a random item from an array
  • randomItemIndex() - returns a tuple of a random item and its index from an array
  • takeRandomItem() - returns a random item from an array and mutates it to remove the item
  • randomizeArray() - returns a copy of the array with its items in a random order