diff --git a/packages/react-reconciler/src/ReactFiberClassComponent.new.js b/packages/react-reconciler/src/ReactFiberClassComponent.new.js
index 4688c10998d17..663b27dfed419 100644
--- a/packages/react-reconciler/src/ReactFiberClassComponent.new.js
+++ b/packages/react-reconciler/src/ReactFiberClassComponent.new.js
@@ -30,7 +30,13 @@ import invariant from 'shared/invariant';
 import {REACT_CONTEXT_TYPE, REACT_PROVIDER_TYPE} from 'shared/ReactSymbols';
 
 import {resolveDefaultProps} from './ReactFiberLazyComponent.new';
-import {DebugTracingMode, StrictMode} from './ReactTypeOfMode';
+import {
+  BlockingMode,
+  ConcurrentMode,
+  DebugTracingMode,
+  NoMode,
+  StrictMode,
+} from './ReactTypeOfMode';
 
 import {
   enqueueUpdate,
@@ -891,7 +897,12 @@ function mountClassInstance(
   }
 
   if (typeof instance.componentDidMount === 'function') {
-    if (__DEV__ && enableDoubleInvokingEffects) {
+    if (
+      __DEV__ &&
+      enableDoubleInvokingEffects &&
+      (workInProgress.mode & (BlockingMode | ConcurrentMode)) !== NoMode
+    ) {
+      // Never double-invoke effects for legacy roots.
       workInProgress.flags |= MountLayoutDev | Update;
     } else {
       workInProgress.flags |= Update;
@@ -965,7 +976,11 @@ function resumeMountClassInstance(
     // If an update was already in progress, we should schedule an Update
     // effect even though we're bailing out, so that cWU/cDU are called.
     if (typeof instance.componentDidMount === 'function') {
-      if (__DEV__ && enableDoubleInvokingEffects) {
+      if (
+        __DEV__ &&
+        enableDoubleInvokingEffects &&
+        (workInProgress.mode & (BlockingMode | ConcurrentMode)) !== NoMode
+      ) {
         workInProgress.flags |= MountLayoutDev | Update;
       } else {
         workInProgress.flags |= Update;
@@ -1012,7 +1027,11 @@ function resumeMountClassInstance(
       }
     }
     if (typeof instance.componentDidMount === 'function') {
-      if (__DEV__ && enableDoubleInvokingEffects) {
+      if (
+        __DEV__ &&
+        enableDoubleInvokingEffects &&
+        (workInProgress.mode & (BlockingMode | ConcurrentMode)) !== NoMode
+      ) {
         workInProgress.flags |= MountLayoutDev | Update;
       } else {
         workInProgress.flags |= Update;
@@ -1022,7 +1041,11 @@ function resumeMountClassInstance(
     // If an update was already in progress, we should schedule an Update
     // effect even though we're bailing out, so that cWU/cDU are called.
     if (typeof instance.componentDidMount === 'function') {
-      if (__DEV__ && enableDoubleInvokingEffects) {
+      if (
+        __DEV__ &&
+        enableDoubleInvokingEffects &&
+        (workInProgress.mode & (BlockingMode | ConcurrentMode)) !== NoMode
+      ) {
         workInProgress.flags |= MountLayoutDev | Update;
       } else {
         workInProgress.flags |= Update;
diff --git a/packages/react-reconciler/src/ReactFiberCommitWork.new.js b/packages/react-reconciler/src/ReactFiberCommitWork.new.js
index 4e9acfae11356..c43c6f8b1363f 100644
--- a/packages/react-reconciler/src/ReactFiberCommitWork.new.js
+++ b/packages/react-reconciler/src/ReactFiberCommitWork.new.js
@@ -2024,6 +2024,8 @@ function commitPassiveMount(
 
 function invokeLayoutEffectMountInDEV(fiber: Fiber): void {
   if (__DEV__ && enableDoubleInvokingEffects) {
+    // We don't need to re-check for legacy roots here.
+    // This function will not be called within legacy roots.
     switch (fiber.tag) {
       case FunctionComponent:
       case ForwardRef:
@@ -2057,6 +2059,8 @@ function invokeLayoutEffectMountInDEV(fiber: Fiber): void {
 
 function invokePassiveEffectMountInDEV(fiber: Fiber): void {
   if (__DEV__ && enableDoubleInvokingEffects) {
+    // We don't need to re-check for legacy roots here.
+    // This function will not be called within legacy roots.
     switch (fiber.tag) {
       case FunctionComponent:
       case ForwardRef:
@@ -2081,6 +2085,8 @@ function invokePassiveEffectMountInDEV(fiber: Fiber): void {
 
 function invokeLayoutEffectUnmountInDEV(fiber: Fiber): void {
   if (__DEV__ && enableDoubleInvokingEffects) {
+    // We don't need to re-check for legacy roots here.
+    // This function will not be called within legacy roots.
     switch (fiber.tag) {
       case FunctionComponent:
       case ForwardRef:
@@ -2113,6 +2119,8 @@ function invokeLayoutEffectUnmountInDEV(fiber: Fiber): void {
 
 function invokePassiveEffectUnmountInDEV(fiber: Fiber): void {
   if (__DEV__ && enableDoubleInvokingEffects) {
+    // We don't need to re-check for legacy roots here.
+    // This function will not be called within legacy roots.
     switch (fiber.tag) {
       case FunctionComponent:
       case ForwardRef:
diff --git a/packages/react-reconciler/src/ReactFiberHooks.new.js b/packages/react-reconciler/src/ReactFiberHooks.new.js
index 67c148ddc0171..bdd0bed4c759d 100644
--- a/packages/react-reconciler/src/ReactFiberHooks.new.js
+++ b/packages/react-reconciler/src/ReactFiberHooks.new.js
@@ -29,7 +29,12 @@ import {
   enableDoubleInvokingEffects,
 } from 'shared/ReactFeatureFlags';
 
-import {NoMode, BlockingMode, DebugTracingMode} from './ReactTypeOfMode';
+import {
+  NoMode,
+  BlockingMode,
+  ConcurrentMode,
+  DebugTracingMode,
+} from './ReactTypeOfMode';
 import {
   NoLane,
   NoLanes,
@@ -485,7 +490,11 @@ export function bailoutHooks(
   lanes: Lanes,
 ) {
   workInProgress.updateQueue = current.updateQueue;
-  if (__DEV__ && enableDoubleInvokingEffects) {
+  if (
+    __DEV__ &&
+    enableDoubleInvokingEffects &&
+    (workInProgress.mode & (BlockingMode | ConcurrentMode)) !== NoMode
+  ) {
     workInProgress.flags &= ~(
       MountPassiveDevEffect |
       PassiveEffect |
@@ -1253,7 +1262,11 @@ function mountEffect(
     }
   }
 
-  if (__DEV__ && enableDoubleInvokingEffects) {
+  if (
+    __DEV__ &&
+    enableDoubleInvokingEffects &&
+    (currentlyRenderingFiber.mode & (BlockingMode | ConcurrentMode)) !== NoMode
+  ) {
     return mountEffectImpl(
       MountPassiveDevEffect | PassiveEffect | PassiveStaticEffect,
       HookPassive,
@@ -1287,7 +1300,11 @@ function mountLayoutEffect(
   create: () => (() => void) | void,
   deps: Array<mixed> | void | null,
 ): void {
-  if (__DEV__ && enableDoubleInvokingEffects) {
+  if (
+    __DEV__ &&
+    enableDoubleInvokingEffects &&
+    (currentlyRenderingFiber.mode & (BlockingMode | ConcurrentMode)) !== NoMode
+  ) {
     return mountEffectImpl(
       MountLayoutDevEffect | UpdateEffect,
       HookLayout,
@@ -1355,7 +1372,11 @@ function mountImperativeHandle<T>(
   const effectDeps =
     deps !== null && deps !== undefined ? deps.concat([ref]) : null;
 
-  if (__DEV__ && enableDoubleInvokingEffects) {
+  if (
+    __DEV__ &&
+    enableDoubleInvokingEffects &&
+    (currentlyRenderingFiber.mode & (BlockingMode | ConcurrentMode)) !== NoMode
+  ) {
     return mountEffectImpl(
       MountLayoutDevEffect | UpdateEffect,
       HookLayout,
diff --git a/packages/react-reconciler/src/ReactFiberWorkLoop.new.js b/packages/react-reconciler/src/ReactFiberWorkLoop.new.js
index 4f40bde182310..a07d0f7031ed8 100644
--- a/packages/react-reconciler/src/ReactFiberWorkLoop.new.js
+++ b/packages/react-reconciler/src/ReactFiberWorkLoop.new.js
@@ -2874,6 +2874,11 @@ function commitDoubleInvokeEffectsInDEV(
   hasPassiveEffects: boolean,
 ) {
   if (__DEV__ && enableDoubleInvokingEffects) {
+    // Never double-invoke effects for legacy roots.
+    if ((fiber.mode & (BlockingMode | ConcurrentMode)) === NoMode) {
+      return;
+    }
+
     setCurrentDebugFiberInDEV(fiber);
     invokeEffectsInDev(fiber, MountLayoutDev, invokeLayoutEffectUnmountInDEV);
     if (hasPassiveEffects) {
@@ -2898,6 +2903,8 @@ function invokeEffectsInDev(
   invokeEffectFn: (fiber: Fiber) => void,
 ): void {
   if (__DEV__ && enableDoubleInvokingEffects) {
+    // We don't need to re-check for legacy roots here.
+    // This function will not be called within legacy roots.
     let fiber = firstChild;
     while (fiber !== null) {
       if (fiber.child !== null) {
diff --git a/packages/react-reconciler/src/__tests__/ReactDoubleInvokeEvents-test.internal.js b/packages/react-reconciler/src/__tests__/ReactDoubleInvokeEvents-test.internal.js
index fddc3744245a3..e5136af4e2406 100644
--- a/packages/react-reconciler/src/__tests__/ReactDoubleInvokeEvents-test.internal.js
+++ b/packages/react-reconciler/src/__tests__/ReactDoubleInvokeEvents-test.internal.js
@@ -11,17 +11,44 @@
 
 let React;
 let ReactFeatureFlags;
-let ReactNoop;
+let ReactTestRenderer;
 let Scheduler;
+let act;
 
 describe('ReactDoubleInvokeEvents', () => {
   beforeEach(() => {
     jest.resetModules();
     React = require('react');
     ReactFeatureFlags = require('shared/ReactFeatureFlags');
-    ReactNoop = require('react-noop-renderer');
+    ReactTestRenderer = require('react-test-renderer');
     Scheduler = require('scheduler');
     ReactFeatureFlags.enableDoubleInvokingEffects = __VARIANT__;
+    act = ReactTestRenderer.unstable_concurrentAct;
+  });
+
+  it('should not double invoke effects in legacy mode', () => {
+    function App({text}) {
+      React.useEffect(() => {
+        Scheduler.unstable_yieldValue('useEffect mount');
+        return () => Scheduler.unstable_yieldValue('useEffect unmount');
+      });
+
+      React.useLayoutEffect(() => {
+        Scheduler.unstable_yieldValue('useLayoutEffect mount');
+        return () => Scheduler.unstable_yieldValue('useLayoutEffect unmount');
+      });
+
+      return text;
+    }
+
+    act(() => {
+      ReactTestRenderer.create(<App text={'mount'} />);
+    });
+
+    expect(Scheduler).toHaveYielded([
+      'useLayoutEffect mount',
+      'useEffect mount',
+    ]);
   });
 
   it('double invoking for effects works properly', () => {
@@ -38,8 +65,12 @@ describe('ReactDoubleInvokeEvents', () => {
 
       return text;
     }
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'mount'} />);
+
+    let renderer;
+    act(() => {
+      renderer = ReactTestRenderer.create(<App text={'mount'} />, {
+        unstable_isConcurrent: true,
+      });
     });
 
     if (__DEV__ && __VARIANT__) {
@@ -58,8 +89,8 @@ describe('ReactDoubleInvokeEvents', () => {
       ]);
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'update'} />);
+    act(() => {
+      renderer.update(<App text={'update'} />);
     });
 
     expect(Scheduler).toHaveYielded([
@@ -69,8 +100,8 @@ describe('ReactDoubleInvokeEvents', () => {
       'useEffect mount',
     ]);
 
-    ReactNoop.act(() => {
-      ReactNoop.render(null);
+    act(() => {
+      renderer.unmount();
     });
 
     expect(Scheduler).toHaveYielded([
@@ -94,8 +125,11 @@ describe('ReactDoubleInvokeEvents', () => {
       return text;
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'mount'} />);
+    let renderer;
+    act(() => {
+      renderer = ReactTestRenderer.create(<App text={'mount'} />, {
+        unstable_isConcurrent: true,
+      });
     });
 
     if (__DEV__ && __VARIANT__) {
@@ -114,8 +148,8 @@ describe('ReactDoubleInvokeEvents', () => {
       ]);
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'update'} />);
+    act(() => {
+      renderer.update(<App text={'update'} />);
     });
 
     expect(Scheduler).toHaveYielded([
@@ -125,8 +159,8 @@ describe('ReactDoubleInvokeEvents', () => {
       'useEffect Two mount',
     ]);
 
-    ReactNoop.act(() => {
-      ReactNoop.render(null);
+    act(() => {
+      renderer.unmount(null);
     });
 
     expect(Scheduler).toHaveYielded([
@@ -152,8 +186,11 @@ describe('ReactDoubleInvokeEvents', () => {
       return text;
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'mount'} />);
+    let renderer;
+    act(() => {
+      renderer = ReactTestRenderer.create(<App text={'mount'} />, {
+        unstable_isConcurrent: true,
+      });
     });
 
     if (__DEV__ && __VARIANT__) {
@@ -172,8 +209,8 @@ describe('ReactDoubleInvokeEvents', () => {
       ]);
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'update'} />);
+    act(() => {
+      renderer.update(<App text={'update'} />);
     });
 
     expect(Scheduler).toHaveYielded([
@@ -183,8 +220,8 @@ describe('ReactDoubleInvokeEvents', () => {
       'useLayoutEffect Two mount',
     ]);
 
-    ReactNoop.act(() => {
-      ReactNoop.render(null);
+    act(() => {
+      renderer.unmount();
     });
 
     expect(Scheduler).toHaveYielded([
@@ -206,8 +243,11 @@ describe('ReactDoubleInvokeEvents', () => {
       return text;
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'mount'} />);
+    let renderer;
+    act(() => {
+      renderer = ReactTestRenderer.create(<App text={'mount'} />, {
+        unstable_isConcurrent: true,
+      });
     });
 
     if (__DEV__ && __VARIANT__) {
@@ -224,8 +264,8 @@ describe('ReactDoubleInvokeEvents', () => {
       ]);
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'update'} />);
+    act(() => {
+      renderer.update(<App text={'update'} />);
     });
 
     expect(Scheduler).toHaveYielded([
@@ -233,8 +273,8 @@ describe('ReactDoubleInvokeEvents', () => {
       'useEffect mount',
     ]);
 
-    ReactNoop.act(() => {
-      ReactNoop.render(null);
+    act(() => {
+      renderer.unmount();
     });
 
     expect(Scheduler).toHaveYielded([]);
@@ -264,8 +304,8 @@ describe('ReactDoubleInvokeEvents', () => {
       }
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App />);
+    act(() => {
+      ReactTestRenderer.create(<App />, {unstable_isConcurrent: true});
     });
 
     if (__DEV__ && __VARIANT__) {
@@ -298,8 +338,11 @@ describe('ReactDoubleInvokeEvents', () => {
       }
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'mount'} />);
+    let renderer;
+    act(() => {
+      renderer = ReactTestRenderer.create(<App text={'mount'} />, {
+        unstable_isConcurrent: true,
+      });
     });
 
     if (__DEV__ && __VARIANT__) {
@@ -312,19 +355,45 @@ describe('ReactDoubleInvokeEvents', () => {
       expect(Scheduler).toHaveYielded(['componentDidMount']);
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'update'} />);
+    act(() => {
+      renderer.update(<App text={'update'} />);
     });
 
     expect(Scheduler).toHaveYielded(['componentDidUpdate']);
 
-    ReactNoop.act(() => {
-      ReactNoop.render(null);
+    act(() => {
+      renderer.unmount();
     });
 
     expect(Scheduler).toHaveYielded(['componentWillUnmount']);
   });
 
+  it('should not double invoke class lifecycles in legacy mode', () => {
+    class App extends React.PureComponent {
+      componentDidMount() {
+        Scheduler.unstable_yieldValue('componentDidMount');
+      }
+
+      componentDidUpdate() {
+        Scheduler.unstable_yieldValue('componentDidUpdate');
+      }
+
+      componentWillUnmount() {
+        Scheduler.unstable_yieldValue('componentWillUnmount');
+      }
+
+      render() {
+        return this.props.text;
+      }
+    }
+
+    act(() => {
+      ReactTestRenderer.create(<App text={'mount'} />);
+    });
+
+    expect(Scheduler).toHaveYielded(['componentDidMount']);
+  });
+
   it('double flushing passive effects only results in one double invoke', () => {
     function App({text}) {
       const [state, setState] = React.useState(0);
@@ -345,8 +414,10 @@ describe('ReactDoubleInvokeEvents', () => {
       return text;
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'mount'} />);
+    act(() => {
+      ReactTestRenderer.create(<App text={'mount'} />, {
+        unstable_isConcurrent: true,
+      });
     });
 
     if (__DEV__ && __VARIANT__) {
@@ -410,8 +481,8 @@ describe('ReactDoubleInvokeEvents', () => {
       return showChild && <Child />;
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App />);
+    act(() => {
+      ReactTestRenderer.create(<App />, {unstable_isConcurrent: true});
     });
 
     if (__DEV__ && __VARIANT__) {
@@ -430,7 +501,7 @@ describe('ReactDoubleInvokeEvents', () => {
       ]);
     }
 
-    ReactNoop.act(() => {
+    act(() => {
       _setShowChild(true);
     });
 
@@ -495,8 +566,11 @@ describe('ReactDoubleInvokeEvents', () => {
       );
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'mount'} />);
+    let renderer;
+    act(() => {
+      renderer = ReactTestRenderer.create(<App text={'mount'} />, {
+        unstable_isConcurrent: true,
+      });
     });
 
     if (__DEV__ && __VARIANT__) {
@@ -519,8 +593,8 @@ describe('ReactDoubleInvokeEvents', () => {
       ]);
     }
 
-    ReactNoop.act(() => {
-      ReactNoop.render(<App text={'mount'} />);
+    act(() => {
+      renderer.update(<App text={'mount'} />);
     });
 
     expect(Scheduler).toHaveYielded([
@@ -530,8 +604,8 @@ describe('ReactDoubleInvokeEvents', () => {
       'useEffect mount',
     ]);
 
-    ReactNoop.act(() => {
-      ReactNoop.render(null);
+    act(() => {
+      renderer.unmount();
     });
 
     expect(Scheduler).toHaveYielded([
diff --git a/packages/react/src/__tests__/ReactProfiler-test.internal.js b/packages/react/src/__tests__/ReactProfiler-test.internal.js
index 191cec9492cec..05d73235b1b38 100644
--- a/packages/react/src/__tests__/ReactProfiler-test.internal.js
+++ b/packages/react/src/__tests__/ReactProfiler-test.internal.js
@@ -4180,7 +4180,11 @@ describe('Profiler', () => {
               const interactions = SchedulerTracing.unstable_getCurrent();
               expect(interactions.size).toBe(1);
               interaction = Array.from(interactions)[0];
-              ReactTestRenderer.create(<Component />);
+              ReactTestRendererAct(() => {
+                ReactTestRenderer.create(<Component />, {
+                  unstable_isConcurrent: true,
+                });
+              });
             },
           );
           Scheduler.unstable_flushAll();