jankdefer 🖥🔥

It's like domready, except it defers loading until the page framerate stabilizes. The idea is that if requestAnimationFrame is running slowly, then the page has either not loaded yet or the page is in a background tab.

This script ensures requestAnimationFrame runs at least 50fps for several frames before calling back.

See also: [requestIdleCallback|https://developer.mozilla.org/en-US/docs/Web/API/Window/requestIdleCallback]

Usage

Basic usage should be good enough for most scenarios:

const jankdefer = require('jankdefer');

jankdefer(myFunction);

Usage with options:

const jankdefer = require('jankdefer');

jankdefer(myFunction, {
  framerateTarget: 50,
  timeout: 3000,
  threshold: 5,
  debug: false,
});

Default options

Property	Default	Description
framerateTarget	50	Wait until the system is running at least 50fps. (Some slower devices do not run at 60)
timeout	3000	Number of milliseconds after which the function will run anyway.
threshold	5	Wait at least this many successful runs before calling back.
debug	false	Print debug info if you want to understand what's happening.