Google Updates Global Site Tag (gtag.js) and Google Tag Manager (gtm.js) to Set a New Same-Site Cookie on Advertisers’ Web Domainshttps://support.google.com
Google has just announced that they are updating the global site tag (gtag.js) and Google Tag Manager (gtm.js) to set a new same-site cookie on advertisers’ web domains to help improve how they attribute conversions back to ads.
the new cookie will be unique and limited to users on your site only. Starting in May 2021, this first-party cookie will enable more accurate attribution of conversions, including instances where a user might engage with more than one of your ads before converting.
Advertisers can opt out of our tagging solutions that use first-party cookies at any time by disabling conversion linking. Learn more.