Fix runtime prefetch isPartial byte stripping when deployed#90272
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unstubbable merged 1 commit intocanaryfrom Feb 21, 2026
Merged
Fix runtime prefetch isPartial byte stripping when deployed#90272unstubbable merged 1 commit intocanaryfrom
isPartial byte stripping when deployed#90272unstubbable merged 1 commit intocanaryfrom
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Make `stripIsPartialByte` resilient to responses that don't have the
leading `isPartial` marker byte. Instead of unconditionally consuming
the first byte, it now checks whether it's a recognized marker ('~' or
'#') and leaves the stream intact when it isn't.
This also removes the `NEXT_IS_PRERENDER_HEADER` guard that previously
prevented byte stripping for fully static responses. On Vercel, the CDN
can add this header to runtime prefetch responses that do contain the
marker byte, which caused the client to skip stripping — corrupting the
RSC stream and preventing dynamic navigation requests.
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Stats from current PR✅ No significant changes detected📊 All Metrics📖 Metrics GlossaryDev Server Metrics:
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📝 Changed Files (8 files)Files with changes:
View diffsapp-page-exp..ntime.dev.jsDiff too large to display app-page-exp..time.prod.jsDiff too large to display app-page-tur..ntime.dev.jsDiff too large to display app-page-tur..time.prod.jsDiff too large to display app-page-tur..ntime.dev.jsDiff too large to display app-page-tur..time.prod.jsDiff too large to display app-page.runtime.dev.jsDiff too large to display app-page.runtime.prod.jsDiff too large to display |
eps1lon
approved these changes
Feb 21, 2026
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Make
stripIsPartialByteresilient to responses that don't have the leadingisPartialmarker byte. Instead of unconditionally consuming the first byte, it now checks whether it's a recognized marker ('~' or '#') and leaves the stream intact when it isn't.This also removes the
NEXT_IS_PRERENDER_HEADERguard that previously prevented byte stripping for fully static responses. On Vercel, the CDN can add this header to runtime prefetch responses that do contain the marker byte, which caused the client to skip stripping — corrupting the RSC stream and preventing dynamic navigation requests.