Fix reversed blog navigation links (#7844)

[kanikaa88]

Summary

Fixes reversed blog navigation links where "Previous" pointed to newer posts and "Next" pointed to older posts (reported in #7844).

Problem

Blog posts in sidebarBlog.json are ordered from newest to oldest (chronologically descending). The getRouteMeta function uses depth-first traversal, which sets:

• prevRoute = routes that come before in traversal (newer posts)
• nextRoute = routes that come after in traversal (older posts)

This caused "Previous" to point to newer posts and "Next" to point to older posts, which is backwards from expected blog navigation UX.

Solution

Swap prevRoute and nextRoute specifically for blog posts (section === 'blog') before passing them to DocsPageFooter. This ensures:

• "Previous" → older posts (back in time) ✅
• "Next" → newer posts (forward in time) ✅

Changes

• Modified Page.tsx to swap routes only for blog section (lines 99-100)
• Other sections (learn, reference, etc.) remain unchanged
• Minimal change - only affects blog navigation

Testing

✅ Verified locally:

• Tested on http://localhost:3000/blog/2025/04/23/react-labs-view-transitions-activity-and-more
• "Previous" correctly points to older post (February 14, 2025)
• "Next" correctly points to newer post (October 1, 2025)
• Navigation works correctly when clicking links

Before fix:

• Previous → October 1, 2025 (newer) ❌
• Next → February 14, 2025 (older) ❌

After fix:

• Previous → February 14, 2025 (older) ✅
• Next → October 1, 2025 (newer) ✅

Fixes #7844

[github-actions]

Size changes

Details

📦 Next.js Bundle Analysis for react-dev

This analysis was generated by the Next.js Bundle Analysis action. 🤖

Five Pages Changed Size

The following pages changed size from the code in this PR compared to its base branch:

Page	Size (compressed)	First Load
/404	128.14 KB (🟡 +15 B)	238.69 KB
/500	128.15 KB (🟡 +15 B)	238.7 KB
/[[...markdownPath]]	130.58 KB (🟡 +15 B)	241.13 KB
/errors	128.39 KB (🟡 +15 B)	238.94 KB
/errors/[errorCode]	128.37 KB (🟡 +15 B)	238.92 KB

Details

Only the gzipped size is provided here based on an expert tip.

First Load is the size of the global bundle plus the bundle for the individual page. If a user were to show up to your website and land on a given page, the first load size represents the amount of javascript that user would need to download. If next/link is used, subsequent page loads would only need to download that page's bundle (the number in the "Size" column), since the global bundle has already been downloaded.

Any third party scripts you have added directly to your app using the <script> tag are not accounted for in this analysis

Next to the size is how much the size has increased or decreased compared with the base branch of this PR. If this percentage has increased by 10% or more, there will be a red status indicator applied, indicating that special attention should be given to this.

[dakshverma23]

LGTM — fixes blog footer nav and clarifies the effects doc. Please add a one-line comment in Page.tsx explaining why next/prev are swapped for blog posts.

[kanikaa88]

Done! Added the comment. Thanks for the review! 🙌

LGTM — fixes blog footer nav and clarifies the effects doc. Please add a one-line comment in Page.tsx explaining why next/prev are swapped for blog posts.