Investigate Webpack's `sideEffects: false`

Reading up on [tree shaking,](https://webpack.js.org/guides/tree-shaking/#mark-the-file-as-side-effect-free) something caught my eye in a StackOverflow answer:

>Although technically this example is very primitive, when you start dealing with Frameworks or Libraries that re-export a bunch of modules up to a higher level for Developer Experience (Three.js, Angular, lodash-es, etc), then performance gains are significant when (if they are sideEffect free module exports) you flag them in this manner.

>A "side effect" is defined as code that performs a special behavior when imported, other than exposing one or more exports. An example of this are polyfills, which affect the global scope and usually do not provide an export.

https://stackoverflow.com/a/49203452/92446

The issue names no repository files, tests, or entry points. Start with the linked Webpack tree-shaking guide and Stack Overflow answer, then determine whether this repository can safely use sideEffects: false. Done means recording the applicability and the configuration or follow-up change required.

Written by the indexing model from the issue text.