Astro Info
Astro v6.4.2
Node v24.15.0
System macOS (arm64)
Package Manager pnpm
Output static
Adapter @astrojs/node
Integrations @astrojs/react
@astrojs/mdx
@astroscope/boot (v0.6.10)
astro-icon
@astrojs/sitemap
@astrojs/markdoc (v1.0.4)
astro:md
@astrojs/svelte (v8.1.1)
If this issue only occurs in one browser, which browser is a problem?
No response
Describe the Bug
I have some global stylesheets included (and preloaded) in the head of every page (tailwind theme, css layers etc). After adding ClientRouter to the head, on page transitions all of those styles were gone.
After talking to my robot this is what it identified:
Root cause confirmed. Let me read Astro's server-island replacer (bottom of that file) carefully — it walks previousSibling backward removing nodes until it hits the comment marker. Let me verify the components and the mechanism, then fix.
The mechanism is now clear:
DataDog and GTM are server:defer server islands placed in <head>.- Astro's ClientRouter head swap (
swapHeadElements) only moves element children (document.head.children) — it does not carry over the HTML comment delimiters (<!--[if astro]>server-island-start<![endif]-->) that bound each island.
- After navigation, the island's
<script> re-runs replaceServerIsland, which deletes every previousSibling until it finds that comment marker. Since the marker was lost in the head swap, it walks back and deletes the preceding global stylesheets (global.css, layers.css).
This is why only the shared global s vanish, and only after navigation. Let me confirm the components are just scripts, then move them to the <body> (where the whole element — comments included — is swapped intact).
I've confirmed it that by moving the server:deferred components to the body page transitions work fully.
What's the expected result?
Pages should include all the same head tags as the previous page even with server:deferred components.
Link to Minimal Reproducible Example
https://stackblitz.com/edit/github-xpcko3w4?file=src%2Flayouts%2FLayout.astro
Participation
Astro Info
If this issue only occurs in one browser, which browser is a problem?
No response
Describe the Bug
I have some global stylesheets included (and preloaded) in the head of every page (tailwind theme, css layers etc). After adding ClientRouter to the head, on page transitions all of those styles were gone.
After talking to my robot this is what it identified:
I've confirmed it that by moving the server:deferred components to the body page transitions work fully.
What's the expected result?
Pages should include all the same head tags as the previous page even with server:deferred components.
Link to Minimal Reproducible Example
https://stackblitz.com/edit/github-xpcko3w4?file=src%2Flayouts%2FLayout.astro
Participation