At my workplace we only ever used it once to build a skinnable white label customer support widget for about a dozen of our client's websites. It's a webcompon

At my workplace we only ever used it once to build a skinnable white label customer support widget for about a dozen of our client's websites. It's a webcomponent that gracefully degrades to es5 + polyfills for IE (this was years ago). Getting the rollup build to work correctly was a bitch and a half, but it turned out nice and it's still in use today.