Cross-Boundary Tracking: Recap And Verify

5 questions. Answer all of them, then submit; you need 4 of 5 to pass.

1. 1. Visitors go from yourdomain.com to checkout on payhost.com and GA4 shows the checkout as a new session with payhost referrals. What fixes it?

   Blocking payhost.com in the referral exclusion list onlyConfiguring both domains in the Google tag so the linker carries the session acrossFiring the purchase tag from yourdomain.com insteadSetting the same Measurement ID cannot help across domains
2. 2. After configuring cross-domain measurement, what visible change confirms the linker is working?

   Outgoing links to the second domain gain a _gl parameter carrying the client IDThe second domain sets a cookie named _crossdomainGA4 shows a linker event in realtimeThe browser console logs 'linker active'
3. 3. A widget inside a third-party iframe fires a conversion, but GTM on the parent page never sees it. Why not, and what is the bridge?

   The iframe loads too late; a Window Loaded trigger fixes itThe iframe's clicks bubble to the parent, so an All Elements trigger worksGTM cannot see into a cross-origin iframe; the iframe postMessages the parent, and a listener relays it into the parent dataLayerYou must install a second GTM container inside the iframe and merge the data later
4. 4. In the postMessage relay listener, why validate event.origin before pushing to the dataLayer?

   It speeds up message deliveryAny page or frame can postMessage your window, so without the check an attacker could inject fake events into your trackingBrowsers require it or the message is droppedIt converts the message payload to JSON
5. 5. What information does the _gl linker parameter actually carry between domains?

   The visitor's granted consent choicesThe full GTM container configurationThe visitor's personal details for the checkout formGA4's client identity, so the destination can continue the same session instead of starting a new one