What is CLS by cookies on/off
CLS by cookies on/off shows Cumulative Layout Shift (CLS) grouped by whether the user’s browser had cookies enabled or disabled during their visit.
This breakdown helps you see if layout stability depends on cookie access — which is increasingly relevant as more users browse in incognito mode, use privacy tools, or block tracking by default.
Browsers with cookies disabled often block related features like localStorage or personalization scripts, which can change how content is rendered.
Layout shifts may increase when cookies are off due to:
Personalization or A/B testing scripts failing to run, leading to delayed content insertion
Consent banners appearing late or taking up space unexpectedly
Page layout reacting differently without user-specific settings
Fallback experiences loading in an unstable or less-optimized way
Healthy CLS by cookies on/off sample
If CLS is low for both states (cookies on and off), your site handles privacy-conscious users well and ensures layout stability for all.
Unhealthy CLS by cookies on/off sample
High CLS when cookies are disabled often indicates:
Consent banners pushing content after load
Personalization logic breaking layout without a cookie fallback
Critical UI loading too late when fallback mode is triggered
High CLS when cookies are enabled may point to:
Heavy personalization elements loading late (e.g. chat widgets, ads)
Delayed A/B content that shifts the layout
Extra scripts or third-party tools altering layout post-load
Either case creates visual instability and hurts user experience.
Resolving unhealthy CLS by cookies on/off
Go-to action plan to resolve an unhealthy CLS by cookies on/off:
Ask Uxi to analyze your CLS by cookies on/off values and suggest improvements
Use Filters to isolate the segments and analyze affected components.
Simulate CLS of the suspected breakdown to see if fixing it will resolve the CLS by cookies on/off. If yes, this is where the resolution focus should be.
Use an automated CLS optimization tool like Navigation AI to improve your CLS by cookies on/off values
Once you’ve improved CLS, set an alert to be the first to know if it starts worsening again.
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