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As soon CDomainCS is activated, our CMP injects an additional iFrame into the website and stores the consent information not only in the websites local storage but also in the iFrame's local storage. While the user switches to another (sub-)domain, the iFrames local storage is checked and if consent information is found, the consent information from the iFrame is stored into the local storage of the new (sub-)domain.
Improved consent sharing between subdomains
Modern browsers are causing that website visitors might still see the CMP again when switching to another subdomain as they block the shared iframe provided by Usercentrics (s. Browser related restrictions). The following linked section in the documentation describes the needed steps to prevent this from happening: Improved consent sharing between subdomains.
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