Gatsby Next and React 19 support. #788
Description
In gatsbyjs/gatsby#39180 (comment)
The gatsby team just shipped a preview of React 19 support in gatsby@next.
Let's give it a try and report back with any issues.
👉🏼 To upgrade, follow the upgrade guide in #39306, but use @next instead of @latest. For example:
npm install --legacy-peer-deps gatsby@next gatsby-plugin-postcss@next # ... any other gatsby-* deps
It would be especially helpful if you could apply this upgrade ↑ first (staying on React 18), let all tests run and then upgrade to React 19 separately in a later iteration. This will help validate all scenarios.