ally.js
ally.js is a JavaScript library designed to simplify the implementation of accessibility features in web applications. It provides standard functions that the web platform lacks, helping developers manage focus, identify focusable or tabbable elements, trap focus navigation, and handle ShadowDOM interactions. It also includes a polyfill for the :focus-within CSS selector and utilities to determine focus changes and element visibility, making complex accessibility tasks easier to handle.
Checked on Oct 19, 2026.
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