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fix: link stylesheets and fonts in the head even when SSR is disabled#15718

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teemingc merged 4 commits into
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fix-spa-fouc
Apr 16, 2026
Merged

fix: link stylesheets and fonts in the head even when SSR is disabled#15718
teemingc merged 4 commits into
mainfrom
fix-spa-fouc

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@teemingc teemingc commented Apr 16, 2026

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closes #13307
related to rust-lang/crates.io#13436

This PR ensures that stylesheets and fonts are eagerly loaded even if SSR is disabled. This helps prevent FOUC. In the case of fallback pages, we only load the root layout which already applies to every page and is safe to load even if we don't know what route is being rendered until CSR kicks in.


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🦋 Changeset detected

Latest commit: 1f43587

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package
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@sveltejs/kit Patch

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@teemingc teemingc changed the title fix: link stylesheets and fonts for CSR-only pages fix: link stylesheets and fonts in the head for CSR-only pages Apr 16, 2026
@teemingc teemingc changed the title fix: link stylesheets and fonts in the head for CSR-only pages fix: link stylesheets and fonts in the head even when SSR is disabled Apr 16, 2026
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@teemingc teemingc merged commit 50cc685 into main Apr 16, 2026
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@teemingc teemingc deleted the fix-spa-fouc branch April 16, 2026 19:50
This was referenced Apr 16, 2026
elliott-with-the-longest-name-on-github pushed a commit that referenced this pull request Apr 23, 2026
This PR was opened by the [Changesets
release](https://github.com/changesets/action) GitHub action. When
you're ready to do a release, you can merge this and the packages will
be published to npm automatically. If you're not ready to do a release
yet, that's fine, whenever you add more changesets to main, this PR will
be updated.


# Releases
## @sveltejs/kit@2.58.0

### Minor Changes

- breaking: require `limit` in `requested` (as originally intended)
([#15739](#15739))


- feat: `RemoteQueryFunction` gains an optional third generic parameter
`Validated` (defaulting to `Input`) that represents the argument type
after schema validation/transformation
([#15739](#15739))


- breaking: `requested` now yields `{ arg, query }` entries instead of
the validated argument
([#15739](#15739))

### Patch Changes

- fix: allow `query().current`, `.error`, `.loading`, and `.ready` to
work in non-reactive contexts
([#15699](#15699))


- fix: prevent `deep_set` crash on nullish nested values
([#15600](#15600))


- fix: restore correct `RemoteFormFields` typing for nullable array
fields (e.g. when a schema uses `.default([])`), so `.as('checkbox')`
and friends work again
([#15723](#15723))


- fix: don't warn about removed SSI comments in `transformPageChunk`
([#15695](#15695))

Server-side include (SSI) directives like `<!--#include virtual="..."
-->` are HTML comments that are replaced by servers such as nginx.
Previously, removing them in `transformPageChunk` would trigger a false
positive warning about breaking Svelte's hydration. Since SSI comments
always start with `<!--#` and Svelte's hydration comments never do, they
can be safely excluded from the check.

- Change enhance function return type from void to MaybePromise<void>.
([#15710](#15710))


- fix: throw an error when `resolve` is called with an external URL
([#15733](#15733))


- fix: avoid FOUC for CSR-only pages by loading styles and fonts before
CSR starts ([#15718](#15718))


- fix: reset form result on redirect
([#15724](#15724))

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Turbo87 added a commit to Turbo87/crates.io that referenced this pull request Apr 28, 2026
Temporary revert to verify the FOUC fix in 2.58.0 (sveltejs/kit#15718)
is what's causing Percy snapshots to capture unstyled content after
client-side navigation.
Turbo87 added a commit to Turbo87/crates.io that referenced this pull request Apr 28, 2026
SvelteKit 2.58.0 (sveltejs/kit#15718) emits root-layout stylesheets
in the server HTML to avoid a flash of unstyled content. With
`paths.relative: true` (the default), those hrefs are relative to
the request URL. Percy preserves the attribute strings verbatim and
renders the snapshot at a different URL, so the relative hrefs no
longer resolve and the snapshot comes out unstyled.

Force absolute paths under `PLAYWRIGHT=1` to keep Percy snapshots
stable.
@teemingc teemingc linked an issue May 21, 2026 that may be closed by this pull request
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FOUC in SPA on (re)load. Different link preloads for static rendering

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