A polyfill for IE11 or browsers that have a WeakMap, but not a WeakSet.
- CDN via https://unpkg.com/@ungap/weakset
- ESM via
import WeakSet from '@ungap/weakset' - CJS via
const WeakSet = require('@ungap/weakset')
Compatible down to IE9, works well with ES5 shim upfront in IE8 (and maybe lower too).