| title | What's New in DevTools (Microsoft Edge 140) |
|---|---|
| description | Invalidation count in CSS selector stats, in the Performance tool. Emulate the 'Save-Data' header in Network conditions. And more. |
| author | MSEdgeTeam |
| ms.author | msedgedevrel |
| ms.topic | conceptual |
| ms.service | microsoft-edge |
| ms.subservice | devtools |
| ms.date | 09/04/2025 |
These are the latest features in the Stable release of Microsoft Edge DevTools.
In the Performance tool, the CSS Selector stats tab's table has a new column: Invalidation count. The Invalidation count column shows an aggregated count of DOM nodes that are matched by a CSS selector that were invalidated and had their style recalculated. A DOM node can be invalidated multiple times, by multiple CSS selectors.
During a recalculate style event, the browser may invalidate many DOM nodes, based on a given CSS selector. Inefficient CSS selectors can impact your webpage's performance. If you have high style-recalculation costs, that might be caused by over-invalidation. You can use this new insight to identify CSS selectors that have a high invalidation count, and reduce over-invalidation by refining your CSS style rules.
See also:
Microsoft Edge 140 also includes the following updates from the Chromium project: