You will need to use a bundler like Rollup, Parcel, or Webpack to include this library in the build of Chrome extension.
See rollup-plugin-chrome-extension
for
an easy way use Rollup to build your Chrome extension!
npm i @extend-chrome/events-rxjs
import { contextMenus } from '@extend-chrome/events-rxjs'
contextMenus.clickStream.subscribe((clickEvent) => {
console.log('click', clickEvent)
})