When running a Chrome Audit from within the developer console, Lighthouse (the engine behind the audit) displays the following:
Does not use passive listeners to improve scrolling performance
Consider marking your touch and wheel event listeners as `passive` to improve your page's scroll performance. [Learn more](https://developers.google.com/web/tools/lighthouse/audits/passive-event-listeners).
amp.Cloudflare.com/viewer/.../amp-viewer.js
Making the change will not only help my OCD by allowing the test to score 100% but also improve the performance of scrolling.