Step 5. Test and preview sGTM configuration

1. Open preview mode in web and server containers.

• Go to https://tagmanager.google.com/
• Open your ​server GTM container​ → click Preview.
• In a different browser tab, open your web GTM container → click Preview → enter your website’s URL. 

This will start the web debug session. Your website will open in a new window with the GTM debug panel active at the bottom.

2. Trigger a request from your website. 

• Perform actions that trigger tags. By simply loading the page, you’ve triggered the page_view event. Other simple possible actions include reloading the page or clicking a button. Such events will show in your debugger.
• In web GTM Preview, click on the event. Under Tags Fired, find the tag you configured to send data to your server (e.g., Google Analytics 4 tag). If it fired, it means a request was successfully sent to your server container.

3. Check incoming requests in the server GTM Preview.

• Go back to the ​server GTM Preview tab​ you opened in the first step.
• If you see events coming from your website domain, the setup works and requests are successfully reaching your sGTM container hosted on Stape.
• Click on the incoming request. Check the ​Tags Fired​ tab to see that your server-side tags (like the GA4 tag) have activated. 

• In the fired tag, check the ​Outgoing HTTP Requests​ tab to see the request that your server container successfully sent to Google Analytics. 

If you see that outgoing request, it means that the event data has passed from your website, through your server container, and on to the final destination.