Multi-Tab localStorage Race Condition Fixed in Mood-Tracking App InnerHue

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A developer working on InnerHue, a mood-tracking app using Zustand and localStorage, discovered that opening the app in two browser tabs caused mood entries to randomly disappear or get overwritten. The root cause was a classic race condition: each tab held its own stale in-memory snapshot, and whichever tab wrote to localStorage last would overwrite the other's data. The fix involved adding a window storage event listener to trigger store rehydration whenever another tab updated the shared key, keeping all tabs in sync. A second bug was also uncovered in the same code path, where React Strict Mode's double-invocation of effects caused duplicate mood entries to be created; a useRef guard was added to prevent this. Both fixes were shipped together in a single pull request, highlighting the importance of testing state management under concurrent, multi-tab conditions.

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Developer fixes null-body crash in Formbricks survey SDK flagged by Sentry

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

Klick.tools Launches No-Signup QR Code and URL Shortener Platform with Open API

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