Updated how we measure and report Core Web Vitals metrics to provide more accurate data and better browser support. These changes improve the reliability of your performance metrics moving forward.
Safari Browser Support
All Core Web Vitals metrics are now available in Safari, with one exception: Cumulative Layout Shift (CLS). Safari doesn’t yet provide native support for CLS measurement, which is a browser limitation that affects all analytics platforms. When viewing reports for Safari traffic, CLS data will display as unavailable.
Changes in Marfeel Compass
We’ve corrected how CLS values are calculated to ensure accuracy. Previously, some CLS scores were showing inaccurate values that didn’t accurately represent page stability. Reports now reflect true layout shift measurements, giving you reliable data for optimization decisions.
What This Means for Your Workflow
Your Web Vitals reports will now show more accurate data across all browsers:
- Safari users: All metrics available except CLS (which will show as unavailable)
- CLS measurements: Now showing accurate layout stability scores that may be higher than previous readings
These updates ensure you’re working with precise metrics when analyzing and improving user experience across different browsers.