React · Senior · Question 24 of 75
Why doesn't an already-shown Suspense fallback appear during a transition inside startTransition?
- ✓Correct answer: React keeps the old UI until the new one is ready instead of swapping in a spinner
- 2Inside a transition, Suspense is disabled until the end of the session
- 3The fallback is shown, but too briefly to notice
Explanation
If already displayed content suspends because of an urgent update, React shows the fallback. In a transition it prefers to keep the previous screen (with isPending for an indicator), so skeletons don't "flash". Navigation in Suspense-based routers works this way.