How do I install a visitor ID tag on Gatsby?
On Gatsby, your visitor identification tag goes in: <Script> component from 'gatsby' OR customize src/html.js (fallback method). The install itself takes minutes; the part that goes wrong on Gatsby is below.
Where the tag goes
- <Script> component from 'gatsby' OR customize src/html.js (fallback method).
- Paste your vendor’s tag snippet exactly as issued. Do not wrap it in extra script tags or reformat it.
- Publish or deploy, then verify (below) before trusting data.
What breaks visitor tracking on Gatsby?
Default strategy loads script after page hydration; analytics scripts may miss pageviews if not configured with beforeInteractive.
How do you verify the tag fires?
gatsby build && gatsby serve, open http://localhost:9000, check DevTools for script execution.
Then run through the labeled QA checklist before you rely on the numbers, and set expectations with the match-rate calculator — no vendor identifies every visitor.