Edit page button links are broken - missing /blob/ in URL

[JamesNK]

Description

The "Edit page" button at the bottom of documentation pages generates broken links. The URL is missing /blob/ between the repository name and the branch.

Example

Page: https://aspire.dev/whats-new/aspire-13-4/

Current (broken) link:
https://github.com/microsoft/aspire.dev/main/src/frontend/src/content/docs/whats-new/aspire-13-4.mdx

Expected link:
https://github.com/microsoft/aspire.dev/blob/main/src/frontend/src/content/docs/whats-new/aspire-13-4.mdx

Impact

Users clicking the "Edit page" link get a 404 on GitHub instead of being taken to the source file for editing.

[IEvangelist]

Triage — confirmed in production

Reproduced the bug on the live page. The rendered Edit page anchor on https://aspire.dev/whats-new/aspire-13-4/ is:

<a href="https://github.com/microsoft/aspire.dev/main/src/frontend/src/content/docs/whats-new/aspire-13-4.mdx"
   class="sl-flex print:hidden ..." data-tour-target="edit-page">Edit page</a>

Missing the /edit/ (or /blob/) segment between aspire.dev and main. GitHub 404s the URL.

What's puzzling

The source config looks correct — src/frontend/astro.config.mjs has:

editLink: { baseUrl: 'https://github.com/microsoft/aspire.dev/edit/main/src/frontend/' },

…and the custom src/frontend/src/components/starlight/EditLink.astro just re-uses Astro.locals.starlightRoute.editUrl via <DefaultEditLink>. So Starlight's default should produce …/edit/main/src/frontend/src/content/docs/whats-new/aspire-13-4.mdx, yet the rendered HTML drops /edit/.

Likely suspects (in order of probability):

1. A plugin in astro.config.mjs mutating editUrl (most likely starlight-page-actions or starlight-llms-txt).
2. A routeMiddleware rewrite in src/route-data-middleware.ts.
3. A build-step env override (PUBLIC_REPO_URL / REPO_URL) being concatenated as \$\{repoUrl\}/\$\{branch\}/\$\{path\} somewhere — Note that MicrosoftFooter.astro and Head.astro both build URLs from PUBLIC_REPO_URL; Head.astro's computeSourceUrl correctly uses \$\{repoUrl\}/blob/\$\{commit\}/\$\{path\}, but a similar helper somewhere may be dropping the verb segment.

Suggested approach

1. npm run build in src/frontend and grep the generated HTML for aspire.dev/main/ to confirm the bug reproduces locally.
2. Bisect by temporarily disabling the Starlight plugins one at a time in astro.config.mjs to identify the mutator.
3. Fix the offending plugin call/middleware so the rendered editUrl keeps the editLink.baseUrl intact.
4. Add a regression test under src/frontend/tests/unit/ that snapshots the rendered EditLink href and asserts it starts with https://github.com/microsoft/aspire.dev/edit/main/.

Confirmed working examples (for sanity):

• <meta name="git-source-url" content="https://github.com/microsoft/aspire.dev/blob/<sha>/src/frontend/src/content/docs/whats-new/aspire-13-4.mdx"> — built by Head.astro::computeSourceUrl, ✅ correct.
• Built on commit SHA link in Footer.astro → …/commit/<sha>, ✅ correct.

cc @IEvangelist for visibility — happy to hand this off if the plugin bisect turns out hairier than expected.

[IEvangelist]

I don't experience that issue, is that because I have write access to the repo?

[JamesNK]

Now it's working. /edit/ is part of the URL which wasn't there before:

https://github.com/microsoft/aspire.dev/edit/main/src/frontend/src/content/docs/whats-new/aspire-13-4.mdx