{"id":657,"slug":"scheduler-yield-limited-baseline-may-2026","title":"scheduler.yield() is Limited Availability — Chrome 129+, Edge, Firefox; Safari has not shipped. Use scheduler-polyfill.","kind":"reference","scope":"business","status":"current","audiences":["claude-code","candid-team"],"topics":["inp-optimization","build-tooling"],"reference_body":"**Claim:** `scheduler.yield()` for breaking up long tasks (any client-side work over ~50ms) is Limited Availability as of May 2026.\n\n**Verbatim (MDN Scheduler.yield page):** *\"Limited availability — This feature is not Baseline because it does not work in some of the most widely-used browsers.\"*\n\n**Support:** Chrome 129+, Edge, Firefox; Safari has not shipped.\n\n**Confidence:** Verified.\n\n**Pattern:** use the official `scheduler-polyfill` package for cross-browser production code. Wraps the native API where available and falls back to `setTimeout(0)` everywhere else.\n\n**Threshold to drop the polyfill:** when Safari ships native support.","rationale_body":null,"metadata":null,"links":{"outgoing":[{"slug":"inp-150ms-target-not-200ms-floor","title":"Candid build standard: INP ≤ 150ms target (200ms is the failing floor); LCP ≤ 2.0s; CLS ≤ 0.05","kind":"rule","scope":"business","link_type":"relates-to"}],"incoming":[]},"created_at":"2026-05-22T21:24:18.320Z","updated_at":"2026-05-22T21:24:18.320Z"}