[Onyx] Fix extra mount render introduced in useOnyx v3.0.59

[cristipaval]

Description

Onyx v3.0.59 (react-native-onyx#756) added a state reset inside useOnyx's subscribe callback to fix stale data when dynamically switching keys. However, the reset runs unconditionally — including on initial mount — which causes useSyncExternalStore to see a new snapshot reference after subscription, triggering one extra render per useOnyx hook.

This was caught by reassure performance tests in this CI run during the Onyx bump PR.

To unblock the bump to 3.0.59 (and all subsequent versions), a patch was applied in E/App (#87738): patches/react-native-onyx+3.0.59.patch. The fix needs to be upstreamed into react-native-onyx so the patch can be removed.

Related

• Parent issue: [Due for payment 2026-04-28] [$250] [Onyx Audit] Fix useOnyx state not resetting on key change in getSnapshot() #85416
• Onyx PR that introduced the regression: react-native-onyx#756
• E/App bump PR with patch workaround: Bump onyx to 3.0.59 #87738

Issue Owner

Current Issue Owner: @VickyStash

[VickyStash]

Thank you for creating an issue!
I'm going to push the fix on the onyx side when #87738 passes staging testing!

[melvin-bot]

@Krishna2323 Whoops! This issue is 2 days overdue. Let's get this updated quick!

[VickyStash]

Not overdue! I'm going to prepare a PR for the Onyx soon

[cristipaval]

No overdue, Melv.

[VickyStash]

Updates:

• I've tried to re-apply the patch changes to Onyx, but unfortunately now two tests are failing (they wasn't when patch was created). It looks like it's due to some conflicts with the lately merged PR. I've asked @kubabutkiewicz to help me here, as I also have some other issues in active work.