Chrome DevTools: The new CSS Tracker panel, an analysis of your used/unused CSS during page interactionLast updated: 27th September 2019
The "CSS Tracker" Panel in DevTools is an enhancement of the CSS Coverage feature.
This panel helps identify what CSS was used/unused in a recording session. After recording, you get a general overview of used/unused CSS and the ability to quickly navigate to the point in code where a particular CSS rule is found.
Update: Visual Shadow Editor is in Chrome Stable!