fix: handle <svelte:head> rendered asynchronously#17052
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🦋 Changeset detectedLatest commit: e621f1a 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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Ocean-OS
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Oct 28, 2025
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In an async world, we have no guarantees about the order in which
<svelte:head>content renders. Our current approach of just finding the next block of existing content inside<head>, in order to hydrate it, does not work under these conditions.This takes a different tack — we use the hash of the filename (which should match between SSR and CSR unless you're doing something very strange) to find a block to hydrate. Most of the time this will be the exact right block, but the failure mode is that the
<svelte:head>for the first<Foo />instance gets hydrated with the content for the second<Foo />instance, and vice versa. This, to me, is acceptable — the end result is the same.Before submitting the PR, please make sure you do the following
feat:,fix:,chore:, ordocs:.packages/svelte/src, add a changeset (npx changeset).Tests and linting
pnpm testand lint the project withpnpm lint