Preliminary Checks

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Summary

Hi Gatsby Team,

I'm writing to report an issue with the Tailwind CSS installation instructions provided in the Gatsby documentation.

It appears the guide is significantly outdated:

• The current documentation refers to Tailwind CSS v3, while Tailwind CSS v4 has been released and features a different installation process.
• The link provided in your documentation, intended to direct users to the official "Install Tailwind CSS with Gatsby" guide on the Tailwind CSS website, is currently broken and leads to an error 404.
• The current documentation is mentioning "tailwind.config.js" which is not a part of Tailwind CSS v4 anymore.

Steps to Resolve this Issue

1. Updating the documentation to the new Tailwind CSS stable version 4
2. If it is not planned to update to Tailwind CSS v4 in the documentation, at least change the link mentioned above to the legacy documentation of Tailwind CSS v3 available at https://v3.tailwindcss.com/docs/guides/gatsby