diff --git a/packages/react-devtools-shared/src/devtools/ContextMenu/useContextMenu.js b/packages/react-devtools-shared/src/devtools/ContextMenu/useContextMenu.js
index 1a457f0de2c14..977b2801bb4ed 100644
--- a/packages/react-devtools-shared/src/devtools/ContextMenu/useContextMenu.js
+++ b/packages/react-devtools-shared/src/devtools/ContextMenu/useContextMenu.js
@@ -22,7 +22,7 @@ export default function useContextMenu({
   data: Object,
   id: string,
   onChange?: OnChangeFn,
-  ref: {current: ElementRef<*> | null},
+  ref: {current: ElementRef<any> | null},
 }) {
   const {showMenu} = useContext<RegistryContextType>(RegistryContext);
 
diff --git a/packages/react-devtools-shared/src/devtools/views/Profiler/ChartNode.js b/packages/react-devtools-shared/src/devtools/views/Profiler/ChartNode.js
index e26b73ec8c4bc..31ea3f83b598c 100644
--- a/packages/react-devtools-shared/src/devtools/views/Profiler/ChartNode.js
+++ b/packages/react-devtools-shared/src/devtools/views/Profiler/ChartNode.js
@@ -16,10 +16,10 @@ type Props = {
   height: number,
   isDimmed?: boolean,
   label: string,
-  onClick: (event: SyntheticMouseEvent<*>) => mixed,
-  onDoubleClick?: (event: SyntheticMouseEvent<*>) => mixed,
-  onMouseEnter: (event: SyntheticMouseEvent<*>) => mixed,
-  onMouseLeave: (event: SyntheticMouseEvent<*>) => mixed,
+  onClick: (event: SyntheticMouseEvent<any>) => mixed,
+  onDoubleClick?: (event: SyntheticMouseEvent<any>) => mixed,
+  onMouseEnter: (event: SyntheticMouseEvent<any>) => mixed,
+  onMouseLeave: (event: SyntheticMouseEvent<any>) => mixed,
   placeLabelAboveNode?: boolean,
   textStyle?: Object,
   width: number,
diff --git a/packages/react-devtools-shared/src/devtools/views/Profiler/CommitFlamegraphListItem.js b/packages/react-devtools-shared/src/devtools/views/Profiler/CommitFlamegraphListItem.js
index f30a294fd7e44..b40ce91fa56f8 100644
--- a/packages/react-devtools-shared/src/devtools/views/Profiler/CommitFlamegraphListItem.js
+++ b/packages/react-devtools-shared/src/devtools/views/Profiler/CommitFlamegraphListItem.js
@@ -41,7 +41,7 @@ function CommitFlamegraphListItem({data, index, style}: Props): React.Node {
   const {lineHeight} = useContext(SettingsContext);
 
   const handleClick = useCallback(
-    (event: SyntheticMouseEvent<*>, id: number, name: string) => {
+    (event: SyntheticMouseEvent<EventTarget>, id: number, name: string) => {
       event.stopPropagation();
       selectFiber(id, name);
     },
diff --git a/packages/react-devtools-shared/src/devtools/views/Profiler/Tooltip.js b/packages/react-devtools-shared/src/devtools/views/Profiler/Tooltip.js
index 0d7af3e63ee48..5287cf3d56308 100644
--- a/packages/react-devtools-shared/src/devtools/views/Profiler/Tooltip.js
+++ b/packages/react-devtools-shared/src/devtools/views/Profiler/Tooltip.js
@@ -17,7 +17,7 @@ export default function Tooltip({
   const tooltipRef = useRef(null);
 
   // update the position of the tooltip based on current mouse position
-  const updateTooltipPosition = (event: SyntheticMouseEvent<*>) => {
+  const updateTooltipPosition = (event: SyntheticMouseEvent<EventTarget>) => {
     const element = tooltipRef.current;
     if (element != null) {
       // first find the mouse position
@@ -30,7 +30,7 @@ export default function Tooltip({
     }
   };
 
-  const onMouseMove = (event: SyntheticMouseEvent<*>) => {
+  const onMouseMove = (event: SyntheticMouseEvent<EventTarget>) => {
     updateTooltipPosition(event);
   };
 
@@ -86,7 +86,7 @@ function getTooltipPosition(element, mousePosition) {
 // method used to find the current mouse position inside the container
 function getMousePosition(
   relativeContainer,
-  mouseEvent: SyntheticMouseEvent<*>,
+  mouseEvent: SyntheticMouseEvent<EventTarget>,
 ) {
   if (relativeContainer !== null) {
     // Position within the nearest position:relative container.
diff --git a/packages/react-devtools-shared/src/hooks/parseHookNames/loadSourceAndMetadata.js b/packages/react-devtools-shared/src/hooks/parseHookNames/loadSourceAndMetadata.js
index 3e08302c157b8..652549253c7c7 100644
--- a/packages/react-devtools-shared/src/hooks/parseHookNames/loadSourceAndMetadata.js
+++ b/packages/react-devtools-shared/src/hooks/parseHookNames/loadSourceAndMetadata.js
@@ -134,7 +134,7 @@ function decodeBase64String(encoded: string): Object {
 
 function extractAndLoadSourceMapJSON(
   locationKeyToHookSourceAndMetadata: LocationKeyToHookSourceAndMetadata,
-): Promise<*> {
+): Promise<Array<$Call<<T>(p: Promise<T> | T) => T, Promise<void>>>> {
   // Deduplicate fetches, since there can be multiple location keys per source map.
   const dedupedFetchPromises = new Map();
 
@@ -459,7 +459,7 @@ function isUnnamedBuiltInHook(hook: HooksNode) {
 function loadSourceFiles(
   locationKeyToHookSourceAndMetadata: LocationKeyToHookSourceAndMetadata,
   fetchFileWithCaching: FetchFileWithCaching | null,
-): Promise<*> {
+): Promise<Array<$Call<<T>(p: Promise<T> | T) => T, Promise<void>>>> {
   // Deduplicate fetches, since there can be multiple location keys per file.
   const dedupedFetchPromises = new Map();
 
diff --git a/packages/react-devtools-timeline/src/types.js b/packages/react-devtools-timeline/src/types.js
index daf764ad151e1..2a3aa690148e0 100644
--- a/packages/react-devtools-timeline/src/types.js
+++ b/packages/react-devtools-timeline/src/types.js
@@ -13,7 +13,7 @@ import type {ScrollState} from './view-base/utils/scrollState';
 // eslint-disable-next-line no-unused-vars
 type Return_<R, F: (...args: Array<any>) => R> = R;
 /** Get return type of a function. */
-export type Return<T> = Return_<*, T>;
+export type Return<T> = Return_<mixed, T>;
 
 // Project types
 
diff --git a/packages/react-dom-bindings/src/client/ReactDOMHostConfig.js b/packages/react-dom-bindings/src/client/ReactDOMHostConfig.js
index 4b1ff5bf1e6a8..a6c193e17edbe 100644
--- a/packages/react-dom-bindings/src/client/ReactDOMHostConfig.js
+++ b/packages/react-dom-bindings/src/client/ReactDOMHostConfig.js
@@ -7,6 +7,7 @@
  * @flow
  */
 
+import type {EventPriority} from 'react-reconciler/src/ReactEventPriorities';
 import type {DOMEventName} from '../events/DOMEventNames';
 import type {Fiber, FiberRoot} from 'react-reconciler/src/ReactInternalTypes';
 import type {
@@ -209,7 +210,7 @@ export function getChildHostContext(
   return getChildNamespace(parentNamespace, type);
 }
 
-export function getPublicInstance(instance: Instance): * {
+export function getPublicInstance(instance: Instance): Instance {
   return instance;
 }
 
@@ -370,7 +371,7 @@ export function createTextInstance(
   return textNode;
 }
 
-export function getCurrentEventPriority(): * {
+export function getCurrentEventPriority(): EventPriority {
   const currentEvent = window.event;
   if (currentEvent === undefined) {
     return DefaultEventPriority;
diff --git a/packages/react-dom-bindings/src/client/ReactDOMInput.js b/packages/react-dom-bindings/src/client/ReactDOMInput.js
index ec03d75e37afb..96bc16cd66e3a 100644
--- a/packages/react-dom-bindings/src/client/ReactDOMInput.js
+++ b/packages/react-dom-bindings/src/client/ReactDOMInput.js
@@ -415,7 +415,7 @@ function updateNamedCousins(rootNode, props) {
 export function setDefaultValue(
   node: InputWithWrapperState,
   type: ?string,
-  value: *,
+  value: ToStringValue,
 ) {
   if (
     // Focused number inputs synchronize on blur. See ChangeEventPlugin.js
diff --git a/packages/react-dom-bindings/src/events/ReactDOMEventListener.js b/packages/react-dom-bindings/src/events/ReactDOMEventListener.js
index ba2c1e63239de..10e215913b78b 100644
--- a/packages/react-dom-bindings/src/events/ReactDOMEventListener.js
+++ b/packages/react-dom-bindings/src/events/ReactDOMEventListener.js
@@ -7,6 +7,7 @@
  * @flow
  */
 
+import type {EventPriority} from 'react-reconciler/src/ReactEventPriorities';
 import type {AnyNativeEvent} from '../events/PluginModuleType';
 import type {Fiber, FiberRoot} from 'react-reconciler/src/ReactInternalTypes';
 import type {Container, SuspenseInstance} from '../client/ReactDOMHostConfig';
@@ -407,7 +408,7 @@ export function findInstanceBlockingEvent(
   return null;
 }
 
-export function getEventPriority(domEventName: DOMEventName): * {
+export function getEventPriority(domEventName: DOMEventName): EventPriority {
   switch (domEventName) {
     // Used by SimpleEventPlugin:
     case 'cancel':
diff --git a/packages/react-reconciler/src/ReactChildFiber.new.js b/packages/react-reconciler/src/ReactChildFiber.new.js
index 5ccb578da6e55..179310ec46a91 100644
--- a/packages/react-reconciler/src/ReactChildFiber.new.js
+++ b/packages/react-reconciler/src/ReactChildFiber.new.js
@@ -475,7 +475,7 @@ function createChildReconciler(shouldTrackSideEffects): ChildReconciler {
   function updateFragment(
     returnFiber: Fiber,
     current: Fiber | null,
-    fragment: Iterable<*>,
+    fragment: Iterable<React$Node>,
     lanes: Lanes,
     key: null | string,
   ): Fiber {
@@ -750,7 +750,7 @@ function createChildReconciler(shouldTrackSideEffects): ChildReconciler {
   function reconcileChildrenArray(
     returnFiber: Fiber,
     currentFirstChild: Fiber | null,
-    newChildren: Array<*>,
+    newChildren: Array<any>,
     lanes: Lanes,
   ): Fiber | null {
     // This algorithm can't optimize by searching from both ends since we
@@ -917,7 +917,7 @@ function createChildReconciler(shouldTrackSideEffects): ChildReconciler {
   function reconcileChildrenIterator(
     returnFiber: Fiber,
     currentFirstChild: Fiber | null,
-    newChildrenIterable: Iterable<*>,
+    newChildrenIterable: Iterable<mixed>,
     lanes: Lanes,
   ): Fiber | null {
     // This is the same implementation as reconcileChildrenArray(),
diff --git a/packages/react-reconciler/src/ReactChildFiber.old.js b/packages/react-reconciler/src/ReactChildFiber.old.js
index ec2416d0941c6..74abb553458f7 100644
--- a/packages/react-reconciler/src/ReactChildFiber.old.js
+++ b/packages/react-reconciler/src/ReactChildFiber.old.js
@@ -475,7 +475,7 @@ function createChildReconciler(shouldTrackSideEffects): ChildReconciler {
   function updateFragment(
     returnFiber: Fiber,
     current: Fiber | null,
-    fragment: Iterable<*>,
+    fragment: Iterable<React$Node>,
     lanes: Lanes,
     key: null | string,
   ): Fiber {
@@ -750,7 +750,7 @@ function createChildReconciler(shouldTrackSideEffects): ChildReconciler {
   function reconcileChildrenArray(
     returnFiber: Fiber,
     currentFirstChild: Fiber | null,
-    newChildren: Array<*>,
+    newChildren: Array<any>,
     lanes: Lanes,
   ): Fiber | null {
     // This algorithm can't optimize by searching from both ends since we
@@ -917,7 +917,7 @@ function createChildReconciler(shouldTrackSideEffects): ChildReconciler {
   function reconcileChildrenIterator(
     returnFiber: Fiber,
     currentFirstChild: Fiber | null,
-    newChildrenIterable: Iterable<*>,
+    newChildrenIterable: Iterable<mixed>,
     lanes: Lanes,
   ): Fiber | null {
     // This is the same implementation as reconcileChildrenArray(),
diff --git a/packages/react-reconciler/src/ReactFiberClassUpdateQueue.new.js b/packages/react-reconciler/src/ReactFiberClassUpdateQueue.new.js
index 5bf0a7a376cec..6b76bd9453223 100644
--- a/packages/react-reconciler/src/ReactFiberClassUpdateQueue.new.js
+++ b/packages/react-reconciler/src/ReactFiberClassUpdateQueue.new.js
@@ -207,8 +207,8 @@ export function cloneUpdateQueue<State>(
   }
 }
 
-export function createUpdate(eventTime: number, lane: Lane): Update<*> {
-  const update: Update<*> = {
+export function createUpdate(eventTime: number, lane: Lane): Update<mixed> {
+  const update: Update<mixed> = {
     eventTime,
     lane,
 
diff --git a/packages/react-reconciler/src/ReactFiberClassUpdateQueue.old.js b/packages/react-reconciler/src/ReactFiberClassUpdateQueue.old.js
index c9918ae104c01..0a2d3c4e75117 100644
--- a/packages/react-reconciler/src/ReactFiberClassUpdateQueue.old.js
+++ b/packages/react-reconciler/src/ReactFiberClassUpdateQueue.old.js
@@ -207,8 +207,8 @@ export function cloneUpdateQueue<State>(
   }
 }
 
-export function createUpdate(eventTime: number, lane: Lane): Update<*> {
-  const update: Update<*> = {
+export function createUpdate(eventTime: number, lane: Lane): Update<mixed> {
+  const update: Update<mixed> = {
     eventTime,
     lane,
 
diff --git a/packages/react-reconciler/src/ReactFiberCommitWork.new.js b/packages/react-reconciler/src/ReactFiberCommitWork.new.js
index cd8671e645d1d..18d30effcb704 100644
--- a/packages/react-reconciler/src/ReactFiberCommitWork.new.js
+++ b/packages/react-reconciler/src/ReactFiberCommitWork.new.js
@@ -883,7 +883,7 @@ function commitClassLayoutLifecycles(
 function commitClassCallbacks(finishedWork: Fiber) {
   // TODO: I think this is now always non-null by the time it reaches the
   // commit phase. Consider removing the type check.
-  const updateQueue: UpdateQueue<*> | null = (finishedWork.updateQueue: any);
+  const updateQueue: UpdateQueue<mixed> | null = (finishedWork.updateQueue: any);
   if (updateQueue !== null) {
     const instance = finishedWork.stateNode;
     if (__DEV__) {
@@ -1050,9 +1050,7 @@ function commitLayoutEffectOnFiber(
       if (flags & Callback) {
         // TODO: I think this is now always non-null by the time it reaches the
         // commit phase. Consider removing the type check.
-        const updateQueue: UpdateQueue<
-          *,
-        > | null = (finishedWork.updateQueue: any);
+        const updateQueue: UpdateQueue<mixed> | null = (finishedWork.updateQueue: any);
         if (updateQueue !== null) {
           let instance = null;
           if (finishedWork.child !== null) {
@@ -2521,9 +2519,7 @@ function commitMutationEffectsOnFiber(
       }
 
       if (flags & Callback && offscreenSubtreeIsHidden) {
-        const updateQueue: UpdateQueue<
-          *,
-        > | null = (finishedWork.updateQueue: any);
+        const updateQueue: UpdateQueue<mixed> | null = (finishedWork.updateQueue: any);
         if (updateQueue !== null) {
           deferHiddenCallbacks(updateQueue);
         }
@@ -3015,9 +3011,7 @@ export function reappearLayoutEffects(
 
       // Commit any callbacks that would have fired while the component
       // was hidden.
-      const updateQueue: UpdateQueue<
-        *,
-      > | null = (finishedWork.updateQueue: any);
+      const updateQueue: UpdateQueue<mixed> | null = (finishedWork.updateQueue: any);
       if (updateQueue !== null) {
         commitHiddenCallbacks(updateQueue, instance);
       }
diff --git a/packages/react-reconciler/src/ReactFiberCommitWork.old.js b/packages/react-reconciler/src/ReactFiberCommitWork.old.js
index 284dc4a471653..fb2e9ab00e746 100644
--- a/packages/react-reconciler/src/ReactFiberCommitWork.old.js
+++ b/packages/react-reconciler/src/ReactFiberCommitWork.old.js
@@ -883,7 +883,7 @@ function commitClassLayoutLifecycles(
 function commitClassCallbacks(finishedWork: Fiber) {
   // TODO: I think this is now always non-null by the time it reaches the
   // commit phase. Consider removing the type check.
-  const updateQueue: UpdateQueue<*> | null = (finishedWork.updateQueue: any);
+  const updateQueue: UpdateQueue<mixed> | null = (finishedWork.updateQueue: any);
   if (updateQueue !== null) {
     const instance = finishedWork.stateNode;
     if (__DEV__) {
@@ -1050,9 +1050,7 @@ function commitLayoutEffectOnFiber(
       if (flags & Callback) {
         // TODO: I think this is now always non-null by the time it reaches the
         // commit phase. Consider removing the type check.
-        const updateQueue: UpdateQueue<
-          *,
-        > | null = (finishedWork.updateQueue: any);
+        const updateQueue: UpdateQueue<mixed> | null = (finishedWork.updateQueue: any);
         if (updateQueue !== null) {
           let instance = null;
           if (finishedWork.child !== null) {
@@ -2521,9 +2519,7 @@ function commitMutationEffectsOnFiber(
       }
 
       if (flags & Callback && offscreenSubtreeIsHidden) {
-        const updateQueue: UpdateQueue<
-          *,
-        > | null = (finishedWork.updateQueue: any);
+        const updateQueue: UpdateQueue<mixed> | null = (finishedWork.updateQueue: any);
         if (updateQueue !== null) {
           deferHiddenCallbacks(updateQueue);
         }
@@ -3015,9 +3011,7 @@ export function reappearLayoutEffects(
 
       // Commit any callbacks that would have fired while the component
       // was hidden.
-      const updateQueue: UpdateQueue<
-        *,
-      > | null = (finishedWork.updateQueue: any);
+      const updateQueue: UpdateQueue<mixed> | null = (finishedWork.updateQueue: any);
       if (updateQueue !== null) {
         commitHiddenCallbacks(updateQueue, instance);
       }
diff --git a/packages/react-reconciler/src/ReactInternalTypes.js b/packages/react-reconciler/src/ReactInternalTypes.js
index bee847ce29d63..2ee501d2a433f 100644
--- a/packages/react-reconciler/src/ReactInternalTypes.js
+++ b/packages/react-reconciler/src/ReactInternalTypes.js
@@ -238,7 +238,7 @@ type BaseFiberRootProperties = {
 
   // Node returned by Scheduler.scheduleCallback. Represents the next rendering
   // task that the root will work on.
-  callbackNode: *,
+  callbackNode: any,
   callbackPriority: Lane,
   eventTimes: LaneMap<number>,
   expirationTimes: LaneMap<number>,