facebook · kassens · Jun 16, 2025 · Jun 16, 2025
diff --git a/packages/react-reconciler/src/ReactFiber.js b/packages/react-reconciler/src/ReactFiber.js
@@ -40,7 +40,6 @@ import {
   enableScopeAPI,
   enableLegacyHidden,
   enableTransitionTracing,
-  enableDO_NOT_USE_disableStrictPassiveEffect,
   disableLegacyMode,
   enableObjectFiber,
   enableViewTransition,
@@ -92,7 +91,6 @@ import {
   ProfileMode,
   StrictLegacyMode,
   StrictEffectsMode,
-  NoStrictPassiveEffectsMode,
   SuspenseyImagesMode,
 } from './ReactTypeOfMode';
 import {
@@ -599,12 +597,6 @@ export function createFiberFromTypeAndProps(
         if (disableLegacyMode || (mode & ConcurrentMode) !== NoMode) {
           // Strict effects should never run on legacy roots
           mode |= StrictEffectsMode;
-          if (
-            enableDO_NOT_USE_disableStrictPassiveEffect &&
-            pendingProps.DO_NOT_USE_disableStrictPassiveEffect
-          ) {
-            mode |= NoStrictPassiveEffectsMode;
-          }
         }
         break;
       case REACT_PROFILER_TYPE:

diff --git a/packages/react-reconciler/src/ReactFiberHooks.js b/packages/react-reconciler/src/ReactFiberHooks.js
@@ -55,7 +55,6 @@ import {
   ConcurrentMode,
   StrictEffectsMode,
   StrictLegacyMode,
-  NoStrictPassiveEffectsMode,
 } from './ReactTypeOfMode';
 import {
   NoLane,
@@ -2672,8 +2671,7 @@ function mountEffect(
 ): void {
   if (
     __DEV__ &&
-    (currentlyRenderingFiber.mode & StrictEffectsMode) !== NoMode &&
-    (currentlyRenderingFiber.mode & NoStrictPassiveEffectsMode) === NoMode
+    (currentlyRenderingFiber.mode & StrictEffectsMode) !== NoMode
   ) {
     mountEffectImpl(
       MountPassiveDevEffect | PassiveEffect | PassiveStaticEffect,

diff --git a/packages/react-reconciler/src/ReactFiberWorkLoop.js b/packages/react-reconciler/src/ReactFiberWorkLoop.js
@@ -123,7 +123,6 @@ import {
   ConcurrentMode,
   StrictLegacyMode,
   StrictEffectsMode,
-  NoStrictPassiveEffectsMode,
 } from './ReactTypeOfMode';
 import {
   HostRoot,
@@ -4607,21 +4606,13 @@ function recursivelyTraverseAndDoubleInvokeEffectsInDEV(
 }
 
 // Unconditionally disconnects and connects passive and layout effects.
-function doubleInvokeEffectsOnFiber(
-  root: FiberRoot,
-  fiber: Fiber,
-  shouldDoubleInvokePassiveEffects: boolean = true,
-) {
+function doubleInvokeEffectsOnFiber(root: FiberRoot, fiber: Fiber) {
   setIsStrictModeForDevtools(true);
   try {
     disappearLayoutEffects(fiber);
-    if (shouldDoubleInvokePassiveEffects) {
-      disconnectPassiveEffect(fiber);
-    }
+    disconnectPassiveEffect(fiber);
     reappearLayoutEffects(root, fiber.alternate, fiber, false);
-    if (shouldDoubleInvokePassiveEffects) {
-      reconnectPassiveEffects(root, fiber, NoLanes, null, false, 0);
-    }
+    reconnectPassiveEffects(root, fiber, NoLanes, null, false, 0);
   } finally {
     setIsStrictModeForDevtools(false);
   }
@@ -4640,13 +4631,7 @@ function doubleInvokeEffectsInDEVIfNecessary(
   if (fiber.tag !== OffscreenComponent) {
     if (fiber.flags & PlacementDEV) {
       if (isInStrictMode) {
-        runWithFiberInDEV(
-          fiber,
-          doubleInvokeEffectsOnFiber,
-          root,
-          fiber,
-          (fiber.mode & NoStrictPassiveEffectsMode) === NoMode,
-        );
+        runWithFiberInDEV(fiber, doubleInvokeEffectsOnFiber, root, fiber);
       }
     } else {
       recursivelyTraverseAndDoubleInvokeEffectsInDEV(

diff --git a/packages/react-reconciler/src/ReactTypeOfMode.js b/packages/react-reconciler/src/ReactTypeOfMode.js
@@ -16,7 +16,6 @@ export const ProfileMode = /*                    */ 0b0000010;
 //export const DebugTracingMode = /*             */ 0b0000100; // Removed
 export const StrictLegacyMode = /*               */ 0b0001000;
 export const StrictEffectsMode = /*              */ 0b0010000;
-export const NoStrictPassiveEffectsMode = /*     */ 0b1000000;
 // Keep track of if we're in a SuspenseyImages eligible subtree.
 // TODO: Remove this when enableSuspenseyImages ship where it's always on.
 export const SuspenseyImagesMode = /*            */ 0b0100000;
diff --git a/packages/react-reconciler/src/__tests__/ActivityStrictMode-test.js b/packages/react-reconciler/src/__tests__/ActivityStrictMode-test.js
@@ -55,28 +55,6 @@ describe('Activity StrictMode', () => {
     ]);
   });
 
-  // @gate __DEV__ && enableActivity && enableDO_NOT_USE_disableStrictPassiveEffect
-  it('does not trigger strict effects when disableStrictPassiveEffect is presented on StrictMode', async () => {
-    await act(() => {
-      ReactNoop.render(
-        <React.StrictMode DO_NOT_USE_disableStrictPassiveEffect={true}>
-          <Activity>
-            <Component label="A" />
-          </Activity>
-        </React.StrictMode>,
-      );
-    });
-
-    expect(log).toEqual([
-      'A: render',
-      'A: render',
-      'A: useLayoutEffect mount',
-      'A: useEffect mount',
-      'A: useLayoutEffect unmount',
-      'A: useLayoutEffect mount',
-    ]);
-  });
-
   // @gate __DEV__ && enableActivity
   it('should not trigger strict effects when offscreen is hidden', async () => {
     await act(() => {

diff --git a/packages/react/src/__tests__/ReactStrictMode-test.internal.js b/packages/react/src/__tests__/ReactStrictMode-test.internal.js
@@ -104,52 +104,6 @@ describe('ReactStrictMode', () => {
         ]);
       });
 
-      // @gate enableDO_NOT_USE_disableStrictPassiveEffect
-      it('should include legacy + strict effects mode, but not strict passive effect with disableStrictPassiveEffect', async () => {
-        await act(() => {
-          const container = document.createElement('div');
-          const root = ReactDOMClient.createRoot(container);
-          root.render(
-            <React.StrictMode DO_NOT_USE_disableStrictPassiveEffect={true}>
-              <Component label="A" />
-            </React.StrictMode>,
-          );
-        });
-
-        expect(log).toEqual([
-          'A: render',
-          'A: render',
-          'A: useLayoutEffect mount',
-          'A: useEffect mount',
-          'A: useLayoutEffect unmount',
-          'A: useLayoutEffect mount',
-        ]);
-      });
-
-      // @gate enableDO_NOT_USE_disableStrictPassiveEffect
-      it('should include legacy + strict effects mode, but not strict passive effect with disableStrictPassiveEffect in Suspense', async () => {
-        await act(() => {
-          const container = document.createElement('div');
-          const root = ReactDOMClient.createRoot(container);
-          root.render(
-            <React.StrictMode DO_NOT_USE_disableStrictPassiveEffect={true}>
-              <React.Suspense>
-                <Component label="A" />
-              </React.Suspense>
-            </React.StrictMode>,
-          );
-        });
-
-        expect(log).toEqual([
-          'A: render',
-          'A: render',
-          'A: useLayoutEffect mount',
-          'A: useEffect mount',
-          'A: useLayoutEffect unmount',
-          'A: useLayoutEffect mount',
-        ]);
-      });
-
       it('should allow level to be increased with nesting', async () => {
         await act(() => {
           const container = document.createElement('div');

diff --git a/packages/shared/ReactFeatureFlags.js b/packages/shared/ReactFeatureFlags.js
@@ -260,7 +260,4 @@ export const enableAsyncDebugInfo = __EXPERIMENTAL__;
 // Track which Fiber(s) schedule render work.
 export const enableUpdaterTracking = __PROFILE__;
 
-// Internal only.
-export const enableDO_NOT_USE_disableStrictPassiveEffect = false;
-
 export const ownerStackLimit = 1e4;
diff --git a/packages/shared/forks/ReactFeatureFlags.native-fb.js b/packages/shared/forks/ReactFeatureFlags.native-fb.js
@@ -44,7 +44,6 @@ export const enableAsyncDebugInfo = false;
 export const enableAsyncIterableChildren = false;
 export const enableCPUSuspense = true;
 export const enableCreateEventHandleAPI = false;
-export const enableDO_NOT_USE_disableStrictPassiveEffect = false;
 export const enableMoveBefore = true;
 export const enableFizzExternalRuntime = true;
 export const enableHalt = false;

diff --git a/packages/shared/forks/ReactFeatureFlags.native-oss.js b/packages/shared/forks/ReactFeatureFlags.native-oss.js
@@ -29,7 +29,6 @@ export const enableAsyncDebugInfo = false;
 export const enableAsyncIterableChildren = false;
 export const enableCPUSuspense = false;
 export const enableCreateEventHandleAPI = false;
-export const enableDO_NOT_USE_disableStrictPassiveEffect = false;
 export const enableMoveBefore = true;
 export const enableFizzExternalRuntime = true;
 export const enableHalt = false;

diff --git a/packages/shared/forks/ReactFeatureFlags.test-renderer.js b/packages/shared/forks/ReactFeatureFlags.test-renderer.js
@@ -49,7 +49,6 @@ export const enableLegacyHidden = false;
 
 export const enableTransitionTracing = false;
 
-export const enableDO_NOT_USE_disableStrictPassiveEffect = false;
 export const enableFizzExternalRuntime = true;
 
 export const alwaysThrottleRetries = true;

diff --git a/packages/shared/forks/ReactFeatureFlags.test-renderer.native-fb.js b/packages/shared/forks/ReactFeatureFlags.test-renderer.native-fb.js
@@ -24,7 +24,6 @@ export const enableAsyncDebugInfo = false;
 export const enableAsyncIterableChildren = false;
 export const enableCPUSuspense = true;
 export const enableCreateEventHandleAPI = false;
-export const enableDO_NOT_USE_disableStrictPassiveEffect = false;
 export const enableMoveBefore = false;
 export const enableFizzExternalRuntime = true;
 export const enableHalt = false;

diff --git a/packages/shared/forks/ReactFeatureFlags.test-renderer.www.js b/packages/shared/forks/ReactFeatureFlags.test-renderer.www.js
@@ -50,7 +50,6 @@ export const enableLegacyHidden = false;
 
 export const enableTransitionTracing = false;
 
-export const enableDO_NOT_USE_disableStrictPassiveEffect = false;
 export const enableFizzExternalRuntime = false;
 
 export const alwaysThrottleRetries = true;

diff --git a/packages/shared/forks/ReactFeatureFlags.www-dynamic.js b/packages/shared/forks/ReactFeatureFlags.www-dynamic.js
@@ -17,7 +17,6 @@ export const alwaysThrottleRetries = __VARIANT__;
 export const disableDefaultPropsExceptForClasses = __VARIANT__;
 export const disableLegacyContextForFunctionComponents = __VARIANT__;
 export const disableSchedulerTimeoutInWorkLoop = __VARIANT__;
-export const enableDO_NOT_USE_disableStrictPassiveEffect = __VARIANT__;
 export const enableHiddenSubtreeInsertionEffectCleanup = __VARIANT__;
 export const enableNoCloningMemoCache = __VARIANT__;
 export const enableObjectFiber = __VARIANT__;

diff --git a/packages/shared/forks/ReactFeatureFlags.www.js b/packages/shared/forks/ReactFeatureFlags.www.js
@@ -19,7 +19,6 @@ export const {
   disableDefaultPropsExceptForClasses,
   disableLegacyContextForFunctionComponents,
   disableSchedulerTimeoutInWorkLoop,
-  enableDO_NOT_USE_disableStrictPassiveEffect,
   enableHiddenSubtreeInsertionEffectCleanup,
   enableInfiniteRenderLoopDetection,
   enableNoCloningMemoCache,