Helper Tools & Extensions

DevTools and Preview are enough on their own, but a few tools speed things up. Use them to move faster, not as a replacement for understanding the layers.

Worth installing

• Tag Assistant Companion (Chrome extension), required to debug tags loaded inside an iframe; not needed for top-level pages.
• GA4 / GTM debug extensions that pretty-print hits in the console so you don't parse raw query strings.
• GA4 DebugView (built into GA4), shows events arriving in near real time when debug mode is on.
• Meta Events Manager → Test Events and equivalent vendor tools to confirm receipt at the destination.

Turning on GA4 debug mode

GA4 DebugView only shows a session in debug mode. GTM's Preview enables it automatically; otherwise the GA Debugger extension or a debug_mode parameter does it.