NgRx Store DevTools filter option in v15.0.0: should it also suppress persistence to localStorage?

The Short Answer

No, the NgRx Store DevTools filter should not suppress persistence to localStorage. The filter is a presentation-layer tool designed to reduce UI noise in the Redux DevTools extension; it is not a middleware or a dispatch interceptor. Because persistence typically occurs via meta-reducers or effects within the NgRx Store cycle, the filter has no architectural authority to block those side effects.

Technical Explanation

In NgRx v15.0.0, the DevTools filter operates at the boundary between the Store and the browser extension. When an action is filtered, it is simply omitted from the DevTools timeline and console alerts. However, the action has already been successfully dispatched through the Store's pipeline.

Persistence to localStorage (often implemented via ngrx-store-localstorage or custom meta-reducers) happens during the state transition phase. Since the filter is applied after the state has been updated and the action has been processed by the Store, the persistence logic remains unaware of the filter settings. Attempting to link the two would conflate debugging visibility with application state logic.

Trade-offs: Runtime Noise vs. Persistence Noise

• Runtime Noise: High impact on developer cognitive load. Filtering solves this by cleaning the UI.
• Persistence Noise: Low impact on performance (unless state objects are massive), but can lead to "polluted" saved states if a developer expects a filtered action to have never occurred.

Implementation Recommendation

If the goal is to prevent specific actions from being persisted, you should implement a persistence filter within your meta-reducer or persistence configuration, rather than relying on the DevTools UI filter.

1. Identify the actions that should be excluded from storage.
2. Update your persistence configuration (e.g., the sync` or exclude options in your persistence library) to ignore those action types.
3. For existing persisted entries, a version bump in your state schema or a manual localStorage.clear() is required, as the Store cannot retroactively "un-persist" data based on a new DevTools filter setting.

Verification Step

To confirm this behavior in your environment:

# 1. Apply a filter in DevTools for action 'USER_PING'
# 2. Trigger the 'USER_PING' action in the app
# 3. Open Browser DevTools > Application > Local Storage
# 4. Observe that the state updated despite the action being hidden in the DevTools timeline.

Missing Diagnostic: Are you using a third-party persistence library (like ngrx-store-localstorage) or a custom meta-reducer for your localStorage logic?