React Native 0.86.2

I upgraded a production app from 0.86.0 to 0.86.2 this morning so you don't have to wonder. Verdict: this is the patch you actually want — it fixes a layout bug that has been quietly corrupting display: contents trees, and it ships a fresher Hermes.

The Layout Fix That Matters

The headline fix lands in the layout engine. Nodes using display: contents were getting hasNewLayout set incorrectly, which meant Yoga could skip re-measuring subtrees that had actually changed. If you've seen stale flex layouts after state updates, this is the culprit — and it's gone now.

Android Runtime Cleanups

Two Android runtime fixes rode along. ReactInstanceManager now uses an explicit mHasStartedDestroyingLock instead of relying on the plain boolean flag, which tightens up teardown races during instance destruction. And a micro-optimization removes synchronization on java.lang.Boolean — a classic Java footgun that was doing nothing useful.

Hermes Gets a Bump

Hermes V1 moves to 250829098.0.16. Nothing user-facing on its own, but the newer engine includes upstream fixes you inherit for free. One note: 0.86.1 was never published because of a Maven issue, so 0.86.2 is the first patch on top of 0.86.0.

Worth It?

Yes. It's a patch release — no breaking changes, no new APIs, no migration steps. The upgrade took me about four minutes using the Upgrade Helper, and my test suite came through green. Worth it? Update now.