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## Documentation / Examples

- [x] Make sure the linting passes by running `pnpm build && pnpm lint`
- [x] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)

First of all thanks for this amazing project and all the help you
provide with these examples.

It seems there is code duplication in this example. After some tests
locally seem to _document.js is not necessary for `gtag` to work
properly.


https://github.com/vercel/next.js/blob/9d97a1e34a8a6e09eb127292c730d1a8df63ebb6/examples/with-google-analytics/pages/_app.js#L30-L34


https://github.com/vercel/next.js/blob/9d97a1e34a8a6e09eb127292c730d1a8df63ebb6/examples/with-google-analytics/pages/_document.js#L13-L17

I am aware of #40645 and I would
like to ask @dave-hay, @SukkaW and @ijjk to consider this is still
necessary. If so why then not move all content of the scripts from _app
to _document?

In any case, I am open to adding here some comments explaining what is
the reason for this code duplication if necessary.

<hr/>

Changes that come from  #43897

1. The `event` hashChangeComplete should be removed since `/home` and
`/home/#section` is not new pageview, but just reference to the same
page.

If we go from /home to /home/#section (with a button click or a link for
example) this shouldn't trigger a new page visit on `gtag`.

For this reason, I think we should revert the changes from
#36079. If there is a better
argument of why this should stay I am also open to creating comments to
clarify this on the example since I don't think should be the default
behavior and not useful in most cases.

2. The `id="gtag-init"` was added with no context to the example from
#29530

If there is a reason for this id in the script to existing I am open to
adding a comment that clarifies this since in my experience is not
necessary at all.


Edit: Batching with #43897 as
recommended by
#43897 (comment)

---------

Co-authored-by: JJ Kasper <jj@jjsweb.site>