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[Suggestion]: Suspense is missing a caveat about 300ms delay caused by FALLBACK_THROTTLE_MS #8490
Description
Summary
There is a built-in delay of about 300 ms, controlled by FALLBACK_THROTTLE_MS, before Suspense content appears on the page if the promise is unresolved, but this is not documented.
Page
https://react.dev/reference/react/Suspense
Details
There have been several issues opened in the React repo regarding a 300ms delay in Suspense.
- Bug: React.lazy waits ~300ms before rendering even when the preloaded promise has resolved react/react#36569
FALLBACK_THROTTLE_MSslows tests down significantly - could it be configurable? react/react#30408- [React 19] Suspense throttling behavior (
FALLBACK_THROTTLE_MS) kicks in too often react/react#31819
This is a design decision that should be called out so users can expect it as a caveat.
Activity
ShivaKoushik33 commentedon Jun 24, 2026
Hi, I’d like to work on this documentation change and open a PR to add the suggested caveat about the Suspense fallback throttle. Could a maintainer please assign this issue to me? Thanks.
MaxwellCohen commentedon Jul 22, 2026
Resolved with #8505