What is CLS by cookie name
CLS by cookie name shows how Cumulative Layout Shift (CLS) varies depending on whether a specific cookie is present during a user session. This breakdown helps you connect layout stability to user segments like returning visitors, logged-in states, A/B test groups, feature flags, or personalized experiences—anything your site flags with a cookie.
Only cookies that were detected during the selected period are shown.
This is especially valuable for spotting hidden layout issues that affect specific cohorts. A feature or experiment might seem harmless but can quietly cause shifts for targeted users—hurting UX without being noticed in general testing.
Healthy CLS by cookie name sample
In a healthy breakdown, all cookie variations—or at least the most critical ones—show CLS values in the green. This means no user group is experiencing unexpected layout shifts due to conditional content, experimental features, or personalization logic.
If returning users, logged-in sessions, and test buckets all see stable experiences, your layout delivery is consistent and user-safe.
Unhealthy CLS by cookie name sample
When one or more cookie groups show high CLS, it often reveals layout instability that only affects a specific audience.
These issues are often caused by:
Modals, banners, or UI changes triggered by specific cookies
A/B test variants altering layout without proper fallback or spacing
Personalized components loading late or injecting content post-render
Third-party tools or marketing tags that fire only for certain cookies
Because these shifts don’t happen for all users, they can sneak by unnoticed—hurting the experience and trust of targeted segments.
Resolving unhealthy CLS by cookie name
Go-to action plan to resolve an unhealthy CLS by cookie name:
Ask Uxi to analyze your CLS by cookie name values and suggest improvements
Use Filters to focus on specific cookie groups, then check other CLS breakdowns (like by element or navigation type) to locate the root cause.
Simulate CLS of the suspected breakdown to see if fixing it will resolve the CLS by cookie name. If yes, this is where the resolution focus should be.
Use an automated CLS optimization tool like Navigation AI to improve your CLS by cookie name values
Once you’ve improved CLS, set an alert to be the first to know if it starts worsening again.
Try it yourself
Discover how your website performs with real user data.