diff --git a/.ado/ado-test-cleanup.sh b/.ado/ado-test-cleanup.sh
index d58c56aea87b2c..683194dcc50b25 100755
--- a/.ado/ado-test-cleanup.sh
+++ b/.ado/ado-test-cleanup.sh
@@ -2,7 +2,7 @@
 set -ex
 
 # Script used by the Azure DevOps build agent to cleanup the packager and web socket server
-# after the XCode test step has completed
+# after the Xcode test step has completed
 
 # kill whatever is occupying port 8081 (packager)
 lsof -i tcp:8081 | awk 'NR!=1 {print $2}' | xargs kill
diff --git a/.ado/apple-pr.yml b/.ado/apple-pr.yml
index 6514e5219e2646..10498a87aa98b2 100644
--- a/.ado/apple-pr.yml
+++ b/.ado/apple-pr.yml
@@ -31,6 +31,8 @@ jobs:
       - template: templates/apple-job-javascript.yml
         parameters:
             apply_office_patches: $(apply_office_patches)
+            slice_name: $(slice_name)
+            xcode_version: $(xcode_version)
 
   - job: AppleRNPR
     displayName: Apple React Native PR
@@ -84,6 +86,8 @@ jobs:
           xcode_actions_release: $(xcode_actions_release)
           xcode_destination: $(xcode_destination)
           apply_office_patches: $(apply_office_patches)
+          slice_name: $(slice_name)
+          xcode_version: $(xcode_version)
 
   - job: CliInit
     displayName: Verify react-native-macos-init
diff --git a/.ado/templates/apple-job-javascript.yml b/.ado/templates/apple-job-javascript.yml
index fba8fe60c44875..ccdf9a3ce1f2c8 100644
--- a/.ado/templates/apple-job-javascript.yml
+++ b/.ado/templates/apple-job-javascript.yml
@@ -1,10 +1,16 @@
 parameters:
   apply_office_patches: ''
+  slice_name: ''
+  xcode_version: ''
 
 steps:
   - template: apple-node-setup.yml
 
+  # Task Group: Xcode select proper version
   - template: apple-xcode-select.yml
+    parameters:
+      slice_name: ${{ parameters.slice_name }}
+      xcode_version: ${{ parameters.xcode_version }}
 
   - template: apple-droid-node-patching.yml
     parameters:
diff --git a/.ado/templates/apple-job-react-native.yml b/.ado/templates/apple-job-react-native.yml
index f39d588e6f05e1..c74069067a08e4 100644
--- a/.ado/templates/apple-job-react-native.yml
+++ b/.ado/templates/apple-job-react-native.yml
@@ -7,6 +7,8 @@ parameters:
   xcode_actions_release: ''
   xcode_destination: ''
   apply_office_patches: ''
+  slice_name: ''
+  xcode_version: ''
 
 steps:
   # Clean DerivedData
@@ -18,6 +20,9 @@ steps:
 
   # Task Group: Xcode select proper version
   - template: apple-xcode-select.yml
+    parameters:
+      slice_name: ${{ parameters.slice_name }}
+      xcode_version: ${{ parameters.xcode_version }}
 
   - template: apple-droid-node-patching.yml
     parameters:
diff --git a/.ado/templates/apple-xcode-build.yml b/.ado/templates/apple-xcode-build.yml
index cd6437c749325f..c0ee51376ba7cf 100644
--- a/.ado/templates/apple-xcode-build.yml
+++ b/.ado/templates/apple-xcode-build.yml
@@ -10,7 +10,7 @@ parameters:
 
 steps:
   - task: Xcode@5
-    displayName: 'XCode ${{ parameters.xcode_actions }} ${{ parameters.xcode_configuration }} ${{ parameters.xcode_sdk }} ${{ parameters.xcode_scheme }}'
+    displayName: 'Xcode ${{ parameters.xcode_actions }} ${{ parameters.xcode_configuration }} ${{ parameters.xcode_sdk }} ${{ parameters.xcode_scheme }}'
     inputs:
       actions: '${{ parameters.xcode_actions }}'
       configuration: ${{ parameters.xcode_configuration }}
@@ -21,7 +21,7 @@ steps:
       signingOption: auto
       packageApp: false
       teamId: '$(XCodeSigningMicrosoftTeamID)'
-      args: '-destination "${{ parameters.xcode_destination }}" ONLY_ACTIVE_ARCH=NO -verbose -UseModernBuildSystem=NO -derivedDataPath DerivedData ${{ parameters.xcode_extraArgs }}'
+      args: '-destination "${{ parameters.xcode_destination }}" ONLY_ACTIVE_ARCH=YES -verbose -derivedDataPath DerivedData ${{ parameters.xcode_extraArgs }}'
       exportPath: '$(agent.builddirectory)/output/${{ parameters.xcode_sdk }}/${{ parameters.xcode_configuration }}'
       useXcpretty: ${{ parameters.xcode_useXcpretty }}
       publishJUnitResults: ${{ parameters.xcode_useXcpretty }}
diff --git a/.ado/templates/apple-xcode-select.yml b/.ado/templates/apple-xcode-select.yml
index 5451b1ad0db3bc..09ed6cd29f5c3c 100644
--- a/.ado/templates/apple-xcode-select.yml
+++ b/.ado/templates/apple-xcode-select.yml
@@ -1,8 +1,13 @@
 #
-# Task Group: XCode select proper version
+# Task Group: Xcode select proper version
 #
+
+parameters:
+  slice_name: ''
+  xcode_version: ''
+
 steps:
   - bash: |
-      sudo xcode-select --switch '/Applications/Xcode_11.2.1.app'
-    displayName: 'Switch to XCode 11.2.1'
+      sudo xcode-select --switch '${{ parameters.xcode_version }}'
+    displayName: Switch Xcode version ${{ parameters.slice_name }}
     failOnStderr: true
diff --git a/.ado/variables/mac.yml b/.ado/variables/mac.yml
index f81f780ec1b166..f19c8aff920309 100644
--- a/.ado/variables/mac.yml
+++ b/.ado/variables/mac.yml
@@ -1,2 +1,4 @@
 variables:
-  VmImage: macOS-10.14
+  VmImage: macOS-10.15
+  slice_name: 'Xcode_12_4'
+  xcode_version: '/Applications/Xcode_12.4.app'
\ No newline at end of file
diff --git a/Libraries/ART/React-ART.podspec b/Libraries/ART/React-ART.podspec
index e04351c9dca68a..7f33d56724fba9 100644
--- a/Libraries/ART/React-ART.podspec
+++ b/Libraries/ART/React-ART.podspec
@@ -23,7 +23,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.source_files           = "**/*.{m}"
   s.preserve_paths         = "package.json", "LICENSE", "LICENSE-docs"
diff --git a/Libraries/ActionSheetIOS/React-RCTActionSheet.podspec b/Libraries/ActionSheetIOS/React-RCTActionSheet.podspec
index 1ba2b9c8d4d284..ed7d9fb30ccac5 100644
--- a/Libraries/ActionSheetIOS/React-RCTActionSheet.podspec
+++ b/Libraries/ActionSheetIOS/React-RCTActionSheet.podspec
@@ -24,7 +24,7 @@ Pod::Spec.new do |s|
   s.documentation_url      = "https://reactnative.dev/docs/actionsheetios"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.source_files           = "*.{m}"
   s.preserve_paths          = "package.json", "LICENSE", "LICENSE-docs"
diff --git a/Libraries/Blob/React-RCTBlob.podspec b/Libraries/Blob/React-RCTBlob.podspec
index f13d6b5a403d42..4ccdef4a905a56 100644
--- a/Libraries/Blob/React-RCTBlob.podspec
+++ b/Libraries/Blob/React-RCTBlob.podspec
@@ -26,7 +26,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "*.{m,mm}"
diff --git a/Libraries/Components/AccessibilityInfo/AccessibilityInfo.android.js b/Libraries/Components/AccessibilityInfo/AccessibilityInfo.android.js
index 9a99eb6fb6bae9..07556bf488d3c8 100644
--- a/Libraries/Components/AccessibilityInfo/AccessibilityInfo.android.js
+++ b/Libraries/Components/AccessibilityInfo/AccessibilityInfo.android.js
@@ -52,6 +52,13 @@ const AccessibilityInfo = {
     return Promise.resolve(false);
   },
 
+  /**
+   * macOS only
+   */
+  isHighContrastEnabled: function(): Promise<boolean> {
+    return Promise.resolve(false);
+  },
+
   /**
    * iOS only
    */
diff --git a/Libraries/Components/AccessibilityInfo/AccessibilityInfo.ios.js b/Libraries/Components/AccessibilityInfo/AccessibilityInfo.ios.js
index 9e721a776b75cc..66080bfecca0fa 100644
--- a/Libraries/Components/AccessibilityInfo/AccessibilityInfo.ios.js
+++ b/Libraries/Components/AccessibilityInfo/AccessibilityInfo.ios.js
@@ -85,6 +85,13 @@ const AccessibilityInfo = {
     });
   },
 
+  /**
+   * macOS only
+   */
+  isHighContrastEnabled: function(): Promise<boolean> {
+    return Promise.resolve(false);
+  },
+
   /**
    * Query whether inverted colors are currently enabled.
    *
diff --git a/Libraries/Components/AccessibilityInfo/AccessibilityInfo.macos.js b/Libraries/Components/AccessibilityInfo/AccessibilityInfo.macos.js
index 095cf67c30860b..620f1e33e83d21 100644
--- a/Libraries/Components/AccessibilityInfo/AccessibilityInfo.macos.js
+++ b/Libraries/Components/AccessibilityInfo/AccessibilityInfo.macos.js
@@ -18,6 +18,7 @@ const RCTDeviceEventEmitter = require('../../EventEmitter/RCTDeviceEventEmitter'
 import NativeAccessibilityManager from './NativeAccessibilityManager';
 
 const CHANGE_EVENT_NAME = {
+  highContrastChanged: 'highContrastChanged',
   invertColorsChanged: 'invertColorsChanged',
   reduceMotionChanged: 'reduceMotionChanged',
   reduceTransparencyChanged: 'reduceTransparencyChanged',
@@ -26,6 +27,7 @@ const CHANGE_EVENT_NAME = {
 
 type ChangeEventName = $Keys<{
   change: string,
+  highContrastChanged: string,
   invertColorsChanged: string,
   reduceMotionChanged: string,
   reduceTransparencyChanged: string,
@@ -58,6 +60,22 @@ const AccessibilityInfo = {
     return Promise.resolve(false);
   },
 
+  /**
+   * Query whether high contrast is currently enabled.
+   *
+   * Returns a promise which resolves to a boolean.
+   * The result is `true` when invert color is enabled and `false` otherwise.
+   */
+  isHighContrastEnabled: function(): Promise<boolean> {
+    return new Promise((resolve, reject) => {
+      if (NativeAccessibilityManager) {
+        NativeAccessibilityManager.getCurrentHighContrastState(resolve, reject);
+      } else {
+        reject(reject);
+      }
+    });
+  },
+
   /**
    * Query whether inverted colors are currently enabled.
    *
diff --git a/Libraries/Components/AccessibilityInfo/NativeAccessibilityManager.js b/Libraries/Components/AccessibilityInfo/NativeAccessibilityManager.js
index 0a1abe5792492b..cade5c63acec77 100644
--- a/Libraries/Components/AccessibilityInfo/NativeAccessibilityManager.js
+++ b/Libraries/Components/AccessibilityInfo/NativeAccessibilityManager.js
@@ -22,6 +22,12 @@ export interface Spec extends TurboModule {
     onSuccess: (isGrayscaleEnabled: boolean) => void,
     onError: (error: Object) => void,
   ) => void;
+  // [TODO(macOS ISS#2323203)
+  +getCurrentHighContrastState: (
+    onSuccess: (isHighContrastEnabled: boolean) => void,
+    onError: (error: Object) => void,
+  ) => void;
+  // ]TODO(macOS ISS#2323203)
   +getCurrentInvertColorsState: (
     onSuccess: (isInvertColorsEnabled: boolean) => void,
     onError: (error: Object) => void,
diff --git a/Libraries/FBLazyVector/FBLazyVector.podspec b/Libraries/FBLazyVector/FBLazyVector.podspec
index 2589deedb00f28..316a5c8066e8a7 100644
--- a/Libraries/FBLazyVector/FBLazyVector.podspec
+++ b/Libraries/FBLazyVector/FBLazyVector.podspec
@@ -23,7 +23,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS ISS#2323203)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS ISS#2323203)
   s.source                 = source
   s.source_files           = "**/*.{c,h,m,mm,cpp}"
   s.header_dir             = "FBLazyVector"
diff --git a/Libraries/FBReactNativeSpec/FBReactNativeSpec.podspec b/Libraries/FBReactNativeSpec/FBReactNativeSpec.podspec
index 918eb2f371c314..f77fd854467089 100644
--- a/Libraries/FBReactNativeSpec/FBReactNativeSpec.podspec
+++ b/Libraries/FBReactNativeSpec/FBReactNativeSpec.podspec
@@ -26,7 +26,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS ISS#2323203)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS ISS#2323203)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "**/*.{c,h,m,mm,cpp}"
diff --git a/Libraries/Image/React-RCTImage.podspec b/Libraries/Image/React-RCTImage.podspec
index 3cfb96ee430476..a74baca2cb3545 100644
--- a/Libraries/Image/React-RCTImage.podspec
+++ b/Libraries/Image/React-RCTImage.podspec
@@ -27,7 +27,7 @@ Pod::Spec.new do |s|
   s.documentation_url      = "https://reactnative.dev/docs/image"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "*.{m,mm}"
diff --git a/Libraries/LinkingIOS/React-RCTLinking.podspec b/Libraries/LinkingIOS/React-RCTLinking.podspec
index a262a0f6b4376d..786ecfcfddc781 100644
--- a/Libraries/LinkingIOS/React-RCTLinking.podspec
+++ b/Libraries/LinkingIOS/React-RCTLinking.podspec
@@ -27,7 +27,7 @@ Pod::Spec.new do |s|
   s.documentation_url      = "https://reactnative.dev/docs/linking"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "*.{m,mm}"
diff --git a/Libraries/NativeAnimation/React-RCTAnimation.podspec b/Libraries/NativeAnimation/React-RCTAnimation.podspec
index f79a098a76fa33..b79d854edf7365 100644
--- a/Libraries/NativeAnimation/React-RCTAnimation.podspec
+++ b/Libraries/NativeAnimation/React-RCTAnimation.podspec
@@ -26,7 +26,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "{Drivers/*,Nodes/*,*}.{m,mm}"
diff --git a/Libraries/Network/React-RCTNetwork.podspec b/Libraries/Network/React-RCTNetwork.podspec
index f2275bcb9cd6af..0839802ee3e5d5 100644
--- a/Libraries/Network/React-RCTNetwork.podspec
+++ b/Libraries/Network/React-RCTNetwork.podspec
@@ -26,7 +26,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "*.{m,mm}"
diff --git a/Libraries/PushNotificationIOS/React-RCTPushNotification.podspec b/Libraries/PushNotificationIOS/React-RCTPushNotification.podspec
index 05c056cfea415a..28b0ebfae93201 100644
--- a/Libraries/PushNotificationIOS/React-RCTPushNotification.podspec
+++ b/Libraries/PushNotificationIOS/React-RCTPushNotification.podspec
@@ -27,7 +27,7 @@ Pod::Spec.new do |s|
   s.documentation_url      = "https://reactnative.dev/docs/pushnotificationios"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "*.{m,mm}"
diff --git a/Libraries/RCTRequired/RCTRequired.podspec b/Libraries/RCTRequired/RCTRequired.podspec
index 063d4fce0b2f45..753d67b382a4da 100644
--- a/Libraries/RCTRequired/RCTRequired.podspec
+++ b/Libraries/RCTRequired/RCTRequired.podspec
@@ -23,7 +23,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS ISS#2323203)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS ISS#2323203)
   s.source                 = source
   s.source_files           = "**/*.{c,h,m,mm,cpp}"
   s.header_dir             = "RCTRequired"
diff --git a/Libraries/Settings/React-RCTSettings.podspec b/Libraries/Settings/React-RCTSettings.podspec
index dc8d449d345ca0..42995840793f80 100644
--- a/Libraries/Settings/React-RCTSettings.podspec
+++ b/Libraries/Settings/React-RCTSettings.podspec
@@ -27,7 +27,7 @@ Pod::Spec.new do |s|
   s.documentation_url      = "https://reactnative.dev/docs/settings"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "*.{m,mm}"
diff --git a/Libraries/StyleSheet/PlatformColorValueTypes.macos.js b/Libraries/StyleSheet/PlatformColorValueTypes.macos.js
index 75f52deb457dfc..3e8a05f2222e07 100644
--- a/Libraries/StyleSheet/PlatformColorValueTypes.macos.js
+++ b/Libraries/StyleSheet/PlatformColorValueTypes.macos.js
@@ -19,12 +19,35 @@ export opaque type NativeColorValue = {
     light: ?(ColorValue | ProcessedColorValue),
     dark: ?(ColorValue | ProcessedColorValue),
   },
+  colorWithSystemEffect?: {
+    baseColor: ?(ColorValue | ProcessedColorValue),
+    systemEffect: SystemEffectMacOSPrivate,
+  },
 };
 
 export const PlatformColor = (...names: Array<string>): ColorValue => {
   return {semantic: names};
 };
 
+export type SystemEffectMacOSPrivate =
+  | 'none'
+  | 'pressed'
+  | 'deepPressed'
+  | 'disabled'
+  | 'rollover';
+
+export const ColorWithSystemEffectMacOSPrivate = (
+  color: ColorValue,
+  effect: SystemEffectMacOSPrivate,
+): ColorValue => {
+  return {
+    colorWithSystemEffect: {
+      baseColor: color,
+      systemEffect: effect,
+    },
+  };
+};
+
 export type DynamicColorMacOSTuplePrivate = {
   light: ColorValue,
   dark: ColorValue,
@@ -54,8 +77,20 @@ export const normalizeColorObject = (
       },
     };
     return dynamicColor;
+  } else if (
+    'colorWithSystemEffect' in color &&
+    color.colorWithSystemEffect != null
+  ) {
+    const processColor = require('./processColor');
+    const colorWithSystemEffect = color.colorWithSystemEffect;
+    const colorObject: NativeColorValue = {
+      colorWithSystemEffect: {
+        baseColor: processColor(colorWithSystemEffect.baseColor),
+        systemEffect: colorWithSystemEffect.systemEffect,
+      },
+    };
+    return colorObject;
   }
-
   return null;
 };
 
@@ -72,6 +107,19 @@ export const processColorObject = (
       },
     };
     return dynamicColor;
+  } else if (
+    'colorWithSystemEffect' in color &&
+    color.colorWithSystemEffect != null
+  ) {
+    const processColor = require('./processColor');
+    const colorWithSystemEffect = color.colorWithSystemEffect;
+    const colorObject: NativeColorValue = {
+      colorWithSystemEffect: {
+        baseColor: processColor(colorWithSystemEffect.baseColor),
+        systemEffect: colorWithSystemEffect.systemEffect,
+      },
+    };
+    return colorObject;
   }
   return color;
 };
diff --git a/Libraries/StyleSheet/PlatformColorValueTypesMacOS.js b/Libraries/StyleSheet/PlatformColorValueTypesMacOS.js
index 567205d2320088..5a665d9e99fa56 100644
--- a/Libraries/StyleSheet/PlatformColorValueTypesMacOS.js
+++ b/Libraries/StyleSheet/PlatformColorValueTypesMacOS.js
@@ -22,4 +22,20 @@ export const DynamicColorMacOS = (
 ): ColorValue => {
   throw new Error('DynamicColorMacOS is not available on this platform.');
 };
+
+export type SystemEffectMacOS =
+  | 'none'
+  | 'pressed'
+  | 'deepPressed'
+  | 'disabled'
+  | 'rollover';
+
+export const ColorWithSystemEffectMacOS = (
+  color: ColorValue,
+  effect: SystemEffectMacOS,
+): ColorValue => {
+  throw new Error(
+    'ColorWithSystemEffectMacOS is not available on this platform.',
+  );
+};
 // ]TODO(macOS ISS#2323203)
diff --git a/Libraries/StyleSheet/PlatformColorValueTypesMacOS.macos.js b/Libraries/StyleSheet/PlatformColorValueTypesMacOS.macos.js
index 613ed542aa1e5e..f66e7356951f77 100644
--- a/Libraries/StyleSheet/PlatformColorValueTypesMacOS.macos.js
+++ b/Libraries/StyleSheet/PlatformColorValueTypesMacOS.macos.js
@@ -11,7 +11,10 @@
 'use strict';
 
 import type {ColorValue} from './StyleSheetTypes';
-import {DynamicColorMacOSPrivate} from './PlatformColorValueTypes';
+import {
+  DynamicColorMacOSPrivate,
+  ColorWithSystemEffectMacOSPrivate,
+} from './PlatformColorValueTypes';
 
 export type DynamicColorMacOSTuple = {
   light: ColorValue,
@@ -23,4 +26,18 @@ export const DynamicColorMacOS = (
 ): ColorValue => {
   return DynamicColorMacOSPrivate({light: tuple.light, dark: tuple.dark});
 };
+
+export type SystemEffectMacOS =
+  | 'none'
+  | 'pressed'
+  | 'deepPressed'
+  | 'disabled'
+  | 'rollover';
+
+export const ColorWithSystemEffectMacOS = (
+  color: ColorValue,
+  effect: SystemEffectMacOS,
+): ColorValue => {
+  return ColorWithSystemEffectMacOSPrivate(color, effect);
+};
 // ]TODO(macOS ISS#2323203)
diff --git a/Libraries/Text/React-RCTText.podspec b/Libraries/Text/React-RCTText.podspec
index 276ee8ba25787c..e7a55482a37a05 100644
--- a/Libraries/Text/React-RCTText.podspec
+++ b/Libraries/Text/React-RCTText.podspec
@@ -24,7 +24,7 @@ Pod::Spec.new do |s|
   s.documentation_url      = "https://reactnative.dev/docs/text"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.source_files           = "**/*.{h,m}"
   s.ios.exclude_files      = "**/macOS/*" # TODO(macOS ISS#2323203)
diff --git a/Libraries/TypeSafety/RCTTypeSafety.podspec b/Libraries/TypeSafety/RCTTypeSafety.podspec
index 5cd02a9f8119ca..94d21256cbe7d1 100644
--- a/Libraries/TypeSafety/RCTTypeSafety.podspec
+++ b/Libraries/TypeSafety/RCTTypeSafety.podspec
@@ -26,7 +26,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS ISS#2323203)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS ISS#2323203)
   s.compiler_flags         = folly_compiler_flags
   s.source                 = source
   s.source_files           = "**/*.{c,h,m,mm,cpp}"
diff --git a/Libraries/Vibration/React-RCTVibration.podspec b/Libraries/Vibration/React-RCTVibration.podspec
index 4b4bb0512eae0e..46384ce09e6012 100644
--- a/Libraries/Vibration/React-RCTVibration.podspec
+++ b/Libraries/Vibration/React-RCTVibration.podspec
@@ -27,7 +27,7 @@ Pod::Spec.new do |s|
   s.documentation_url      = "https://reactnative.dev/docs/vibration"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "*.{m,mm}"
diff --git a/README.md b/README.md
index 07bda51d9f120c..ca535ec912a306 100644
--- a/README.md
+++ b/README.md
@@ -35,7 +35,7 @@ You can read more about the macOS implementation in our website - [React Native
 
 ## Requirements
 
-You can run React Native for macOS apps on Mac devices with versions [High Sierra (10.13)](https://www.apple.com/newsroom/2017/09/macos-high-sierra-now-available-as-a-free-update/) or newer.
+You can run React Native for macOS apps on Mac devices with versions Mojave (10.14) or newer.
 
 For a full and detailed list of the system requirements and how to set up your development platform, see our [System Requirements](https://microsoft.github.io/react-native-windows/docs/rnm-dependencies) documentation on our website.
 
diff --git a/RNTester/Podfile b/RNTester/Podfile
index 6dfe6a31a45d94..b9cbc443e1096e 100644
--- a/RNTester/Podfile
+++ b/RNTester/Podfile
@@ -83,19 +83,4 @@ end
 
 post_install do |installer|
   flipper_post_install(installer)
-  installer.pods_project.targets.each do |target|
-    # [TODO(macOS ISS#2323203): the internal Microsoft build pipeline needs iOS arm64e slices
-    if target.platform_name == :ios
-      target.build_configurations.each do |config|
-        (config.build_settings['ARCHS'] ||= ['$(ARCHS_STANDARD)']) << 'arm64e'
-      end
-    end
-    # TODO(macOS ISS#2323203): the internal Microsoft build pipeline needs macOS arm64 slices
-    if target.platform_name == :osx
-      target.build_configurations.each do |config|
-        (config.build_settings['ARCHS'] ||= ['$(ARCHS_STANDARD)']) << ' arm64'
-      end
-    end
-    # ]TODO(macOS ISS#2323203)
-  end
 end
diff --git a/RNTester/Podfile.lock b/RNTester/Podfile.lock
index 6fb054f18fe47b..6eddf3da80b324 100644
--- a/RNTester/Podfile.lock
+++ b/RNTester/Podfile.lock
@@ -516,12 +516,12 @@ EXTERNAL SOURCES:
     :path: "../ReactCommon/yoga"
 
 SPEC CHECKSUMS:
-  boost-for-react-native: dabda8622e76020607c2ae1e65cc0cda8b61479d
+  boost-for-react-native: a110407d9db2642fd2e1bcd7c5a51c81f2521dc9
   CocoaAsyncSocket: 694058e7c0ed05a9e217d1b3c7ded962f4180845
   CocoaLibEvent: 2fab71b8bd46dd33ddb959f7928ec5909f838e3f
-  DoubleConversion: 56a44bcfd14ab2ff66f5a146b2e875eb4b69b19b
-  FBLazyVector: 33306016e21286a3ebf05b2e74758ecb51b487cb
-  FBReactNativeSpec: eba7c1b592e557c3d328af72fcd04fa5ad9dc732
+  DoubleConversion: 2b45d0f8e156a5b02354c8a4062de64d41ccb4e0
+  FBLazyVector: 29fb6e7901d1f0a80f920b6f40e29b459e3ec4d1
+  FBReactNativeSpec: 2abf54e37e2606a820a73b437b997605c563c2ff
   Flipper: be611d4b742d8c87fbae2ca5f44603a02539e365
   Flipper-DoubleConversion: 38631e41ef4f9b12861c67d17cb5518d06badc41
   Flipper-Folly: c12092ea368353b58e992843a990a3225d4533c3
@@ -529,39 +529,39 @@ SPEC CHECKSUMS:
   Flipper-PeerTalk: 116d8f857dc6ef55c7a5a75ea3ceaafe878aadc9
   Flipper-RSocket: 64e7431a55835eb953b0bf984ef3b90ae9fdddd7
   FlipperKit: ab353d41aea8aae2ea6daaf813e67496642f3d7d
-  glog: 1cb7c408c781ae8f35bbababe459b45e3dee4ec1
+  glog: 789873d01e4b200777d0a09bc23d548446758699
   hermes: 12d049af0d8e8379c5b3b54ffb1919d670045bdc
-  libevent: ee9265726a1fc599dea382964fa304378affaa5f
+  libevent: 59938c595b8c19e50c83250628ffed9ebf662183
   OpenSSL-Universal: 8b48cc0d10c1b2923617dfe5c178aa9ed2689355
-  RCT-Folly: 1347093ffe75e152d846f7e45a3ef901b60021aa
-  RCTRequired: c1be2a438c43a3bbaae1c648944e74f09bf7b6df
-  RCTTypeSafety: 8a51d44eafbc4d6b845f4bf158973cb15017af4a
-  React: cd84a8114f257b60d426051214bb220e01f31853
-  React-ART: dc713fc5e6fc9d91111ac8dcc36f423edaf726db
-  React-callinvoker: 22c4350c8d512f0c4d28c652de164d261790eee3
-  React-Core: 301a9137b800e78e100804b201a2751eba784396
-  React-CoreModules: 1f63ebf5afc57f1182c29d071f1d0b36729d3c1e
-  React-cxxreact: 4d4c317d32055a60063d6788962df6d8e5e959a9
-  React-jsi: 5130ca982064487449da1e916815a2ab17c8b5f0
-  React-jsiexecutor: fbc8b1046ca4a8a9b5fc1e92e506a96e22600f5f
-  React-jsinspector: dbed1bb565004515d7470a54673da99cd36d6ac8
-  React-RCTActionSheet: 8d7d186c02a07c96ff8b4193c39c829003d5e401
-  React-RCTAnimation: 769775382fcb0fd801bc0e8c4ba69b112b605e97
-  React-RCTBlob: c0e2dba349e77aa3ccbc99b1c61f0f8ba53b6add
-  React-RCTImage: d1424690347182fd14183d471fb756542b9645b8
-  React-RCTLinking: f8d483d3e8e4bcc2749e67d5f68b8006dfe5eb3d
-  React-RCTNetwork: 7d4f1caaae3b87a9c3e924eeea4805a3bcaf9144
-  React-RCTPushNotification: 03dc947964f5c2a3c53389e7c386b5b8bcef2b17
-  React-RCTSettings: 6be17236bffccbcfa3a57dd961b7682998a92a11
-  React-RCTTest: 0de4043839e8b9782e9ca4c3ecaf7c6dace48027
-  React-RCTText: efcbbf74281e0c42f0c7737c8cc0f148b3cf8983
-  React-RCTVibration: 45f0a1b6780752f516bf81717cfdf901896e93a7
-  React-TurboModuleCxx-RNW: 4da8eb44b10ab3c5bbab9fcb0a8ae415c20ea3c9
-  React-TurboModuleCxx-WinRTPort: 723f549e1b886bae14bf16b6ef8420aef0d3f190
-  ReactCommon: 24aa1f1de935591060e0730148c0d85da7567214
-  Yoga: e009ba9e81fe6c0b4067e62295faa522982b3860
+  RCT-Folly: 55d0039b24e192081ec0b2257f7bd9f42e382fb7
+  RCTRequired: 57e1ef095e22d885256164d8c6df479dbd21da07
+  RCTTypeSafety: f72f3ec5db9ee5fa6bb29fe9f7fa7dacf50adfdf
+  React: b97bad9179f2d53c1c1bb1d0c66e2acef1742872
+  React-ART: 0ad249875e1b8884b3cd1c489e4647ff34996485
+  React-callinvoker: 9d92ac3e7ede9a0a85f037a83910a4d66b0c92ca
+  React-Core: 51a5896743a633f4156873166f8df2ed9cb0b0d5
+  React-CoreModules: e2b16910bbce831fba4ca8ac829b816d82c8eef1
+  React-cxxreact: a32457255e1ec50d5a07f9af396870f4b9ed5bdd
+  React-jsi: 651f42a24396052d7597fec149a7f81ca812165b
+  React-jsiexecutor: bfe7c0dbc6682c6beb1202c0c6afac92493e6cea
+  React-jsinspector: 76b4c121774407834f4e595bffbab9ab2b52b32c
+  React-RCTActionSheet: d2197778c865bbcfb1017ee3fd2c50a19318005b
+  React-RCTAnimation: c9bc756f8fe2bf0b3bd6940c7ab03cd757d8a032
+  React-RCTBlob: 1109c2570e7eb5fb33385b4cca2eec4dc302478c
+  React-RCTImage: 8390b4f788ffc069d0a7c284bb9b21650bc66116
+  React-RCTLinking: 11d1b2a7cbc16e38c717cc4a5e77fe30870ba19f
+  React-RCTNetwork: 5e1de525f5e12e74dae2f34e534dbf2cca1d63d3
+  React-RCTPushNotification: 3d65a4c1e7024261d74c764dd6faff4938cc01cb
+  React-RCTSettings: 73c143d2537688995cac0511e1285f9bec202a46
+  React-RCTTest: f8ad362f336933a7ac2aca51bb72d351b62d0655
+  React-RCTText: dba6bfe53bb0ecf817492cda78f6da8c4677e1ab
+  React-RCTVibration: a1e909ab9ae0b1f4090530e2e90b30ba598d67b4
+  React-TurboModuleCxx-RNW: 18bb71af41fe34c8b12a56bef60aae7ee32b0817
+  React-TurboModuleCxx-WinRTPort: 91af7d60f381ea47e2b43a2c0951175dda50218f
+  ReactCommon: eaa845b24197ed3e1f7a3f77d17cb45d98173975
+  Yoga: 8b5431dfe1c915fb925390f0769410304a86e04c
   YogaKit: f782866e155069a2cca2517aafea43200b01fd5a
 
-PODFILE CHECKSUM: 18ca7d3b0e7db79041574a8bb6200b9e1c2d5359
+PODFILE CHECKSUM: baaa75a5807a228f32c4218f28c9260336518038
 
-COCOAPODS: 1.9.3
+COCOAPODS: 1.10.1
diff --git a/RNTester/RCTTest/React-RCTTest.podspec b/RNTester/RCTTest/React-RCTTest.podspec
index fa90f9eed2ebc2..e59791cae35843 100644
--- a/RNTester/RCTTest/React-RCTTest.podspec
+++ b/RNTester/RCTTest/React-RCTTest.podspec
@@ -26,7 +26,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "**/*.{h,m,mm}"
diff --git a/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testLayoutExample_1-iOS14@2x.png b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testLayoutExample_1-iOS14@2x.png
new file mode 100644
index 00000000000000..b9e88a87ae316d
Binary files /dev/null and b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testLayoutExample_1-iOS14@2x.png differ
diff --git a/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testScrollViewExample_1-iOS14@2x.png b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testScrollViewExample_1-iOS14@2x.png
new file mode 100644
index 00000000000000..be30f368dff242
Binary files /dev/null and b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testScrollViewExample_1-iOS14@2x.png differ
diff --git a/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testSwitchExample_1-iOS14@2x.png b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testSwitchExample_1-iOS14@2x.png
new file mode 100644
index 00000000000000..01aebc6813dcba
Binary files /dev/null and b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testSwitchExample_1-iOS14@2x.png differ
diff --git a/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testTextExample_1-iOS14@2x.png b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testTextExample_1-iOS14@2x.png
new file mode 100644
index 00000000000000..eb37b21e2c5ef0
Binary files /dev/null and b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testTextExample_1-iOS14@2x.png differ
diff --git a/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testViewExample_1-iOS14@2x.png b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testViewExample_1-iOS14@2x.png
new file mode 100644
index 00000000000000..6cb548931249cc
Binary files /dev/null and b/RNTester/RNTesterIntegrationTests/ReferenceImages/RNTester-js-RNTesterApp.ios/testViewExample_1-iOS14@2x.png differ
diff --git a/RNTester/RNTesterPods.xcodeproj/project.pbxproj b/RNTester/RNTesterPods.xcodeproj/project.pbxproj
index 9408341a8587f4..c101a29bc80990 100644
--- a/RNTester/RNTesterPods.xcodeproj/project.pbxproj
+++ b/RNTester/RNTesterPods.xcodeproj/project.pbxproj
@@ -1711,7 +1711,7 @@
 				CODE_SIGN_STYLE = Automatic;
 				DEBUG_INFORMATION_FORMAT = dwarf;
 				EXECUTABLE_PREFIX = lib;
-				MACOSX_DEPLOYMENT_TARGET = 10.15;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				OTHER_CFLAGS = (
@@ -1736,7 +1736,7 @@
 				COPY_PHASE_STRIP = NO;
 				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
 				EXECUTABLE_PREFIX = lib;
-				MACOSX_DEPLOYMENT_TARGET = 10.15;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				MTL_FAST_MATH = YES;
 				OTHER_CFLAGS = (
 					"$(inherited)",
@@ -1931,7 +1931,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				OTHER_CFLAGS = (
@@ -1971,7 +1971,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				MTL_FAST_MATH = YES;
 				OTHER_CFLAGS = (
 					"$(inherited)",
@@ -2005,7 +2005,7 @@
 					"@executable_path/../Frameworks",
 					"@loader_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				OTHER_CFLAGS = (
@@ -2041,7 +2041,7 @@
 					"@executable_path/../Frameworks",
 					"@loader_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				MTL_FAST_MATH = YES;
 				OTHER_CFLAGS = (
 					"$(inherited)",
@@ -2076,7 +2076,7 @@
 					"@executable_path/../Frameworks",
 					"@loader_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				OTHER_CFLAGS = (
@@ -2109,7 +2109,7 @@
 					"@executable_path/../Frameworks",
 					"@loader_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				MTL_FAST_MATH = YES;
 				OTHER_CFLAGS = (
 					"$(inherited)",
diff --git a/RNTester/js/examples/Accessibility/AccessibilityExample.js b/RNTester/js/examples/Accessibility/AccessibilityExample.js
index bf92e28a0c9699..3b68f8884cc023 100644
--- a/RNTester/js/examples/Accessibility/AccessibilityExample.js
+++ b/RNTester/js/examples/Accessibility/AccessibilityExample.js
@@ -739,6 +739,16 @@ class DisplayOptionsStatusExample extends React.Component<{}> {
   state = {};
 
   componentDidMount() {
+    AccessibilityInfo.addEventListener(
+      'highContrastChanged',
+      this._handleHighContrastToggled,
+    );
+    AccessibilityInfo.isHighContrastEnabled().done(isEnabled => {
+      this.setState({
+        highContrastEnabled: isEnabled,
+      });
+    });
+
     AccessibilityInfo.addEventListener(
       'invertColorsChanged',
       this._handleInvertColorsToggled,
@@ -771,6 +781,10 @@ class DisplayOptionsStatusExample extends React.Component<{}> {
   }
 
   componentWillUnmount() {
+    AccessibilityInfo.removeEventListener(
+      'highContrastChanged',
+      this._handleHighContrastToggled,
+    );
     AccessibilityInfo.removeEventListener(
       'invertColorsChanged',
       this._handleInvertColorsToggled,
@@ -785,6 +799,12 @@ class DisplayOptionsStatusExample extends React.Component<{}> {
     );
   }
 
+  _handleHighContrastToggled = isEnabled => {
+    this.setState({
+      highContrastEnabled: isEnabled,
+    });
+  };
+
   _handleInvertColorsToggled = isEnabled => {
     this.setState({
       invertColorsEnabled: isEnabled,
@@ -806,6 +826,12 @@ class DisplayOptionsStatusExample extends React.Component<{}> {
   render() {
     return (
       <View>
+        <View>
+          <Text>
+            High contrast is{' '}
+            {this.state.highContrastEnabled ? 'enabled' : 'disabled'}.
+          </Text>
+        </View>
         <View>
           <Text>
             Invert colors is{' '}
diff --git a/RNTester/js/examples/PlatformColor/PlatformColorExample.js b/RNTester/js/examples/PlatformColor/PlatformColorExample.js
index 6968d0619bc765..33079fcffa8cd0 100644
--- a/RNTester/js/examples/PlatformColor/PlatformColorExample.js
+++ b/RNTester/js/examples/PlatformColor/PlatformColorExample.js
@@ -15,6 +15,7 @@ const ReactNative = require('react-native');
 import Platform from '../../../../Libraries/Utilities/Platform';
 const {
   ColorAndroid,
+  ColorWithSystemEffectMacOS, // TODO(macOS GH#750)
   DynamicColorIOS,
   DynamicColorMacOS,
   PlatformColor,
@@ -352,6 +353,144 @@ function VariantColorsExample() {
   );
 }
 
+// [TODO(macOS GH#750)
+function ColorWithSystemEffectMacOSExample() {
+  function createTable() {
+    let colors = [
+      {label: 'gray', color: 'gray'},
+      {
+        label: "ColorWithSystemEffectMacOS('gray', 'none')",
+        color: ColorWithSystemEffectMacOS('gray', 'none'),
+      },
+      {
+        label: "ColorWithSystemEffectMacOS('gray', 'pressed')",
+        color: ColorWithSystemEffectMacOS('gray', 'pressed'),
+      },
+      {
+        label: "ColorWithSystemEffectMacOS('gray', 'deepPressed')",
+        color: ColorWithSystemEffectMacOS('gray', 'deepPressed'),
+      },
+      {
+        label: "ColorWithSystemEffectMacOS('gray', 'disabled')",
+        color: ColorWithSystemEffectMacOS('gray', 'disabled'),
+      },
+      {
+        label: "ColorWithSystemEffectMacOS('gray', 'rollover')",
+        color: ColorWithSystemEffectMacOS('gray', 'rollover'),
+      },
+      {
+        label: "PlatformColor('systemBlueColor')",
+        color: PlatformColor('systemBlueColor'),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(PlatformColor('systemBlueColor'), 'none')",
+        color: ColorWithSystemEffectMacOS(
+          PlatformColor('systemBlueColor'),
+          'none',
+        ),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(PlatformColor('systemBlueColor'), 'pressed')",
+        color: ColorWithSystemEffectMacOS(
+          PlatformColor('systemBlueColor'),
+          'pressed',
+        ),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(PlatformColor('systemBlueColor'), 'deepPressed')",
+        color: ColorWithSystemEffectMacOS(
+          PlatformColor('systemBlueColor'),
+          'deepPressed',
+        ),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(PlatformColor('systemBlueColor'), 'disabled')",
+        color: ColorWithSystemEffectMacOS(
+          PlatformColor('systemBlueColor'),
+          'disabled',
+        ),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(PlatformColor('systemBlueColor'), 'rollover')",
+        color: ColorWithSystemEffectMacOS(
+          PlatformColor('systemBlueColor'),
+          'rollover',
+        ),
+      },
+      {
+        label: "DynamicColorMacOS({light: 'red', dark: 'blue'})",
+        color: DynamicColorMacOS({light: 'red', dark: 'blue'}),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(DynamicColorMacOS({light: 'red', dark: 'blue'}), 'none')",
+        color: ColorWithSystemEffectMacOS(
+          DynamicColorMacOS({light: 'red', dark: 'blue'}),
+          'none',
+        ),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(DynamicColorMacOS({light: 'red', dark: 'blue'}), 'pressed')",
+        color: ColorWithSystemEffectMacOS(
+          DynamicColorMacOS({light: 'red', dark: 'blue'}),
+          'pressed',
+        ),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(DynamicColorMacOS({light: 'red', dark: 'blue'}), 'deepPressed')",
+        color: ColorWithSystemEffectMacOS(
+          DynamicColorMacOS({light: 'red', dark: 'blue'}),
+          'deepPressed',
+        ),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(DynamicColorMacOS({light: 'red', dark: 'blue'}), 'disabled')",
+        color: ColorWithSystemEffectMacOS(
+          DynamicColorMacOS({light: 'red', dark: 'blue'}),
+          'disabled',
+        ),
+      },
+      {
+        label:
+          "ColorWithSystemEffectMacOS(DynamicColorMacOS({light: 'red', dark: 'blue'}), 'rollover')",
+        color: ColorWithSystemEffectMacOS(
+          DynamicColorMacOS({light: 'red', dark: 'blue'}),
+          'rollover',
+        ),
+      },
+    ];
+
+    let table = [];
+    for (let color of colors) {
+      table.push(
+        <View style={styles.row} key={color.label}>
+          <Text style={styles.labelCell}>{color.label}</Text>
+          <View
+            style={{
+              ...styles.colorCell,
+              backgroundColor: color.color,
+            }}
+          />
+        </View>,
+      );
+    }
+    return table;
+  }
+  return Platform.OS === 'macos' ? (
+    <View style={styles.column}>{createTable()}</View>
+  ) : (
+    <Text style={styles.labelCell}>Not applicable on this platform</Text>
+  );
+} // ]TODO(macOS GH#750)
+
 const styles = StyleSheet.create({
   column: {flex: 1, flexDirection: 'column'},
   row: {flex: 0.75, flexDirection: 'row'},
@@ -398,4 +537,11 @@ exports.examples = [
       return <VariantColorsExample />;
     },
   },
+  // [TODO(macOS GH#750)
+  {
+    title: 'Color With System Effect macOS',
+    render(): React.Element<any> {
+      return <ColorWithSystemEffectMacOSExample />;
+    },
+  }, // ]TODO(macOS GH#750)
 ];
diff --git a/React-Core.podspec b/React-Core.podspec
index c8d1f050fa5c86..beeffd4351756d 100644
--- a/React-Core.podspec
+++ b/React-Core.podspec
@@ -42,7 +42,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS ISS#2323203)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS ISS#2323203)
   s.source                 = source
   s.resource_bundle        = { "AccessibilityResources" => ["React/AccessibilityResources/*.lproj"]}
   s.compiler_flags         = folly_compiler_flags + ' ' + boost_compiler_flags
@@ -86,7 +86,7 @@ Pod::Spec.new do |s|
 
   # [TODO(macOS GH#214)
   s.subspec "Hermes" do |ss|
-    ss.platforms = { :osx => "10.13" }
+    ss.platforms = { :osx => "10.14" }
     ss.source_files = "ReactCommon/hermes/executor/*.{cpp,h}",
                       "ReactCommon/hermes/inspector/*.{cpp,h}",
                       "ReactCommon/hermes/inspector/chrome/*.{cpp,h}",
diff --git a/React.podspec b/React.podspec
index 811e062b143306..daf2d96cb1d394 100644
--- a/React.podspec
+++ b/React.podspec
@@ -36,7 +36,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.preserve_paths         = "package.json", "LICENSE", "LICENSE-docs"
   s.cocoapods_version      = ">= 1.2.0"
diff --git a/React/Base/RCTConvert.m b/React/Base/RCTConvert.m
index 31f973429b5fc0..b5e005b306416a 100644
--- a/React/Base/RCTConvert.m
+++ b/React/Base/RCTConvert.m
@@ -951,6 +951,28 @@ + (RCTUIColor *)NSColor:(id)json
 }
 // ]TODO(macOS ISS#2323203)
 
+// [TODO(macOS GH#750)
+#if TARGET_OS_OSX
+static NSColor *RCTColorWithSystemEffect(NSColor* color, NSString *systemEffectString) {
+    NSColor *colorWithEffect = color;
+    if (systemEffectString != nil) {
+        if ([systemEffectString isEqualToString:@"none"]) {
+            colorWithEffect = [color colorWithSystemEffect:NSColorSystemEffectNone];
+        } else if ([systemEffectString isEqualToString:@"pressed"]) {
+            colorWithEffect = [color colorWithSystemEffect:NSColorSystemEffectPressed];
+        } else if ([systemEffectString isEqualToString:@"deepPressed"]) {
+            colorWithEffect = [color colorWithSystemEffect:NSColorSystemEffectDeepPressed];
+        } else if ([systemEffectString isEqualToString:@"disabled"]) {
+            colorWithEffect = [color colorWithSystemEffect:NSColorSystemEffectDisabled];
+        } else if ([systemEffectString isEqualToString:@"rollover"]) {
+            colorWithEffect = [color colorWithSystemEffect:NSColorSystemEffectRollover];
+        }
+    }
+    return colorWithEffect;
+}
+#endif //TARGET_OS_OSX
+// ]TODO(macOS GH#750)
+
 + (RCTUIColor *)UIColor:(id)json // TODO(OSS Candidate ISS#2710739)
 {
   if (!json) {
@@ -1030,8 +1052,24 @@ + (RCTUIColor *)UIColor:(id)json // TODO(OSS Candidate ISS#2710739)
         RCTLogConvertError(json, @"a UIColor. Expected a dynamic appearance aware color.");
         return nil;
       }
+// [TODO(macOS GH#750)
+#if TARGET_OS_OSX
+    } else if((value = [dictionary objectForKey:@"colorWithSystemEffect"])) {
+        NSDictionary *colorWithSystemEffect = value;
+        id base = [colorWithSystemEffect objectForKey:@"baseColor"];
+        NSColor *baseColor = [RCTConvert UIColor:base];
+        NSString * systemEffectString = [colorWithSystemEffect objectForKey:@"systemEffect"];
+        if (baseColor != nil && systemEffectString != nil) {
+            return RCTColorWithSystemEffect(baseColor, systemEffectString);
+        } else {
+            RCTLogConvertError(
+                json, @"a UIColor.  Expected a color with a system effect string, but got something else");
+            return nil;
+        }
+#endif //TARGET_OS_OSX
+// ]TODO(macOS GH#750)
     } else {
-      RCTLogConvertError(json, @"a UIColor. Expected a semantic color or dynamic appearance aware color.");
+      RCTLogConvertError(json, @"a UIColor. Expected a semantic color, dynamic appearance aware color, or color with system effect"); //TODO(macOS GH#750)
       return nil;
     }
 // ]TODO(macOS ISS#2323203)
diff --git a/React/Base/macOS/RCTDynamicColor.m b/React/Base/macOS/RCTDynamicColor.m
index 31b8e13a160dfd..e6899f63eabf7e 100644
--- a/React/Base/macOS/RCTDynamicColor.m
+++ b/React/Base/macOS/RCTDynamicColor.m
@@ -178,7 +178,9 @@ - (nullable NSColor *)blendedColorWithFraction:(CGFloat)fraction ofColor:(NSColo
 
 - (NSColor *)colorWithSystemEffect:(NSColorSystemEffect)systemEffect NS_AVAILABLE_MAC(10_14)
 {
-  return [[self effectiveColor] colorWithSystemEffect:systemEffect];
+    NSColor *aquaColorWithSystemEffect = [_aquaColor colorWithSystemEffect:systemEffect];
+    NSColor *darkAquaColorWithSystemEffect = [_darkAquaColor colorWithSystemEffect:systemEffect];
+    return [[RCTDynamicColor alloc] initWithAquaColor:aquaColorWithSystemEffect darkAquaColor:darkAquaColorWithSystemEffect];
 }
 
 - (NSUInteger)hash
diff --git a/React/CoreModules/RCTAccessibilityManager.h b/React/CoreModules/RCTAccessibilityManager.h
index 7b5a132d262621..310dd8d0600424 100644
--- a/React/CoreModules/RCTAccessibilityManager.h
+++ b/React/CoreModules/RCTAccessibilityManager.h
@@ -21,6 +21,7 @@ extern NSString *const RCTAccessibilityManagerDidUpdateMultiplierNotification; /
 
 @property (nonatomic, assign) BOOL isBoldTextEnabled;
 @property (nonatomic, assign) BOOL isGrayscaleEnabled;
+@property (nonatomic, assign) BOOL isHighContrastEnabled; // TODO(macOS ISS#2323203) - maps to shouldIncreaseContrast on macOS
 @property (nonatomic, assign) BOOL isInvertColorsEnabled;
 @property (nonatomic, assign) BOOL isReduceMotionEnabled;
 @property (nonatomic, assign) BOOL isReduceTransparencyEnabled;
diff --git a/React/CoreModules/RCTDevSettings.mm b/React/CoreModules/RCTDevSettings.mm
index 849b374db5500c..7c5dc8c9c03042 100644
--- a/React/CoreModules/RCTDevSettings.mm
+++ b/React/CoreModules/RCTDevSettings.mm
@@ -119,7 +119,11 @@ - (void)_reloadWithDefaults:(NSDictionary *)defaultValues
       _settings[key] = defaultValues[key];
     }
   }
-  [_userDefaults setObject:_settings forKey:kRCTDevSettingsUserDefaultsKey];
+
+  // TODO(macOS ISS#2323203): protect against race conditions where another thread holds a mutext trying to set this at the same time
+  RCTExecuteOnMainQueue(^{
+    [self->_userDefaults setObject:self->_settings forKey:kRCTDevSettingsUserDefaultsKey];
+  });
 }
 
 @end
diff --git a/React/CoreModules/React-CoreModules.podspec b/React/CoreModules/React-CoreModules.podspec
index e547a3f1f2852f..30177e3aecc4b8 100644
--- a/React/CoreModules/React-CoreModules.podspec
+++ b/React/CoreModules/React-CoreModules.podspec
@@ -26,7 +26,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS ISS#2323203)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS ISS#2323203)
   s.compiler_flags         = folly_compiler_flags + ' -Wno-nullability-completeness'
   s.source                 = source
   s.source_files           = "**/*.{c,m,mm,cpp}"
diff --git a/React/Modules/MacOS/RCTAccessibilityManager.m b/React/Modules/MacOS/RCTAccessibilityManager.m
index 416048a278c748..58974ffbb2afcd 100644
--- a/React/Modules/MacOS/RCTAccessibilityManager.m
+++ b/React/Modules/MacOS/RCTAccessibilityManager.m
@@ -23,12 +23,12 @@ @implementation RCTAccessibilityManager
 
 static void *AccessibilityVoiceOverChangeContext = &AccessibilityVoiceOverChangeContext;
 
-+ (BOOL)requiresMainQueueSetup 
++ (BOOL)requiresMainQueueSetup
 {
-  return NO;
+  return YES;
 }
 
-- (instancetype)init 
+- (instancetype)init
 {
   if (self = [super init]) {
     [[NSWorkspace sharedWorkspace] addObserver:self
@@ -39,11 +39,11 @@ - (instancetype)init
                                              selector:@selector(accessibilityDisplayOptionsChange:)
                                                  name:NSWorkspaceAccessibilityDisplayOptionsDidChangeNotification
                                                object:nil];
+    _isHighContrastEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldIncreaseContrast];
     _isInvertColorsEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldInvertColors];
     _isReduceMotionEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldReduceMotion];
     _isReduceTransparencyEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldReduceTransparency];
     _isVoiceOverEnabled = [[NSWorkspace sharedWorkspace] isVoiceOverEnabled];
-    
   }
   return self;
 }
@@ -53,7 +53,6 @@ - (void)dealloc
   [[NSWorkspace sharedWorkspace] removeObserver:self
                                      forKeyPath:@"voiceOverEnabled"
                                         context:AccessibilityVoiceOverChangeContext];
-  [[[NSWorkspace sharedWorkspace] notificationCenter] removeObserver:self]; 
 }
 
 RCT_EXPORT_METHOD(announceForAccessibility:(NSString *)announcement)
@@ -67,6 +66,12 @@ - (void)dealloc
                                                 );
 }
 
+RCT_EXPORT_METHOD(getCurrentHighContrastState:(RCTResponseSenderBlock)callback
+                  error:(__unused RCTResponseSenderBlock)error)
+{
+  callback(@[@(_isHighContrastEnabled)]);
+}
+
 RCT_EXPORT_METHOD(getCurrentInvertColorsState:(RCTResponseSenderBlock)callback
                   error:(__unused RCTResponseSenderBlock)error)
 {
@@ -124,9 +129,16 @@ - (void)observeValueForKeyPath:(NSString *)keyPath
 
 - (void)accessibilityDisplayOptionsChange:(NSNotification *)notification
 {
+  BOOL newHighContrastEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldIncreaseContrast];
   BOOL newInvertColorsEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldInvertColors];
   BOOL newReduceMotionEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldReduceMotion];
   BOOL newReduceTransparencyEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldReduceTransparency];
+
+  if (_isHighContrastEnabled != newHighContrastEnabled) {
+    _isHighContrastEnabled = newHighContrastEnabled;
+    [_bridge.eventDispatcher sendDeviceEventWithName:@"highContrastChanged"
+                                                body:@(_isHighContrastEnabled)];
+  }
   if (_isInvertColorsEnabled != newInvertColorsEnabled) {
     _isInvertColorsEnabled = newInvertColorsEnabled;
     [_bridge.eventDispatcher sendDeviceEventWithName:@"invertColorsChanged"
diff --git a/React/Views/RCTViewManager.m b/React/Views/RCTViewManager.m
index 8a41562516976d..fbc4f8c0487ab5 100644
--- a/React/Views/RCTViewManager.m
+++ b/React/Views/RCTViewManager.m
@@ -124,6 +124,24 @@ - (RCTShadowView *)shadowView
   ];
 }
 
+#if TARGET_OS_OSX // [TODO(macOS ISS#2323203)
+RCT_EXPORT_METHOD(focus : (nonnull NSNumber *)viewTag)
+{
+  [self.bridge.uiManager addUIBlock:^(RCTUIManager *uiManager, NSDictionary<NSNumber *, RCTUIView *> *viewRegistry) {
+    RCTUIView *view = viewRegistry[viewTag];
+    [view reactFocus];
+  }];
+}
+
+RCT_EXPORT_METHOD(blur : (nonnull NSNumber *)viewTag)
+{
+  [self.bridge.uiManager addUIBlock:^(RCTUIManager *uiManager, NSDictionary<NSNumber *, RCTUIView *> *viewRegistry) {
+    RCTUIView *view = viewRegistry[viewTag];
+    [view reactBlur];
+  }];
+}
+#endif // ]TODO(macOS ISS#2323203)
+
 #pragma mark - View properties
 
 #if TARGET_OS_TV
diff --git a/ReactCommon/ReactCommon.podspec b/ReactCommon/ReactCommon.podspec
index 0948e9d3da9dc1..82b42b6c0a2280 100644
--- a/ReactCommon/ReactCommon.podspec
+++ b/ReactCommon/ReactCommon.podspec
@@ -28,7 +28,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.header_dir             = "ReactCommon" # Use global header_dir for all subspecs for use_frameworks! compatibility
   s.compiler_flags         = folly_compiler_flags + ' ' + boost_compiler_flags
diff --git a/ReactCommon/callinvoker/React-callinvoker.podspec b/ReactCommon/callinvoker/React-callinvoker.podspec
index c983bfa5980836..21e1d9ed7eeaab 100644
--- a/ReactCommon/callinvoker/React-callinvoker.podspec
+++ b/ReactCommon/callinvoker/React-callinvoker.podspec
@@ -27,7 +27,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.source_files           = "**/*.{cpp,h}"
   s.header_dir             = "ReactCommon"
diff --git a/ReactCommon/cxxreact/React-cxxreact.podspec b/ReactCommon/cxxreact/React-cxxreact.podspec
index 5d79b221dca346..12c0ac858aa5bb 100644
--- a/ReactCommon/cxxreact/React-cxxreact.podspec
+++ b/ReactCommon/cxxreact/React-cxxreact.podspec
@@ -27,7 +27,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.source_files           = "*.{cpp,h}"
   s.exclude_files          = "SampleCxxModule.*"
diff --git a/ReactCommon/jsi/React-jsi.podspec b/ReactCommon/jsi/React-jsi.podspec
index 6bc99df93b3f24..00fa87c93dc1f4 100644
--- a/ReactCommon/jsi/React-jsi.podspec
+++ b/ReactCommon/jsi/React-jsi.podspec
@@ -27,7 +27,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.source_files           = "**/*.{cpp,h}"
   s.exclude_files          = "**/test/*"
diff --git a/ReactCommon/jsiexecutor/React-jsiexecutor.podspec b/ReactCommon/jsiexecutor/React-jsiexecutor.podspec
index b67a03eaca9436..eef1279ac5e33f 100644
--- a/ReactCommon/jsiexecutor/React-jsiexecutor.podspec
+++ b/ReactCommon/jsiexecutor/React-jsiexecutor.podspec
@@ -27,7 +27,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.source_files         = "jsireact/*.{cpp,h}"
   s.compiler_flags         = folly_compiler_flags + ' ' + boost_compiler_flags
diff --git a/ReactCommon/jsinspector/React-jsinspector.podspec b/ReactCommon/jsinspector/React-jsinspector.podspec
index 17677010eeb6a5..ff5e71660cc408 100644
--- a/ReactCommon/jsinspector/React-jsinspector.podspec
+++ b/ReactCommon/jsinspector/React-jsinspector.podspec
@@ -23,7 +23,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Facebook, Inc. and its affiliates"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
   s.source                 = source
   s.source_files           = "*.{cpp,h}"
   s.header_dir             = 'jsinspector'
diff --git a/ReactCommon/yoga/Yoga.podspec b/ReactCommon/yoga/Yoga.podspec
index d2943e6138f4e6..38e087939f71ad 100644
--- a/ReactCommon/yoga/Yoga.podspec
+++ b/ReactCommon/yoga/Yoga.podspec
@@ -43,7 +43,7 @@ Pod::Spec.new do |spec|
   ]
 
   # Pinning to the same version as React.podspec.
-  spec.platforms = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" }
+  spec.platforms = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" }
 
   # Set this environment variable when *not* using the `:path` option to install the pod.
   # E.g. when publishing this spec to a spec repo.
diff --git a/ReactTurboModuleCxx/React-TurboModuleCxx-RNW.podspec b/ReactTurboModuleCxx/React-TurboModuleCxx-RNW.podspec
index 5367ab41e65ece..42dac31a0dcced 100644
--- a/ReactTurboModuleCxx/React-TurboModuleCxx-RNW.podspec
+++ b/ReactTurboModuleCxx/React-TurboModuleCxx-RNW.podspec
@@ -13,7 +13,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://github.com/microsoft/react-native-windows"
   s.license                = package["license"]
   s.author                 = "Microsoft Corporation"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" }
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" }
   s.compiler_flags         = folly_compiler_flags
   s.source                 = { :git => 'https://github.com/microsoft/react-native-windows.git',
                                :commit => "d9077991441889ddaa18a8af6a2cc8514ca7714d" }
diff --git a/ReactTurboModuleCxx/React-TurboModuleCxx-WinRTPort.podspec b/ReactTurboModuleCxx/React-TurboModuleCxx-WinRTPort.podspec
index 3becd32bef960c..8e0bfc601d8107 100644
--- a/ReactTurboModuleCxx/React-TurboModuleCxx-WinRTPort.podspec
+++ b/ReactTurboModuleCxx/React-TurboModuleCxx-WinRTPort.podspec
@@ -21,7 +21,7 @@ Pod::Spec.new do |s|
   s.homepage               = "https://github.com/microsoft/react-native-macos"
   s.license                = package["license"]
   s.author                 = "Microsoft Corporation"
-  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" }
+  s.platforms              = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" }
   s.compiler_flags         = folly_compiler_flags
   s.source                 = source
 
diff --git a/index.js b/index.js
index db266061e3083a..a250d1b8e7c05d 100644
--- a/index.js
+++ b/index.js
@@ -99,6 +99,7 @@ import typeof processColor from './Libraries/StyleSheet/processColor';
 import typeof {PlatformColor} from './Libraries/StyleSheet/PlatformColorValueTypes';
 import typeof {DynamicColorIOS} from './Libraries/StyleSheet/PlatformColorValueTypesIOS';
 import typeof {DynamicColorMacOS} from './Libraries/StyleSheet/PlatformColorValueTypesMacOS'; // TODO(macOS ISS#2323203)
+import typeof {ColorWithSystemEffectMacOS} from './Libraries/StyleSheet/PlatformColorValueTypesMacOS'; // TODO(macOS GH#750)
 import typeof {ColorAndroid} from './Libraries/StyleSheet/PlatformColorValueTypesAndroid';
 import typeof RootTagContext from './Libraries/ReactNative/RootTagContext';
 import typeof DeprecatedColorPropType from './Libraries/DeprecatedPropTypes/DeprecatedColorPropType';
@@ -496,10 +497,16 @@ module.exports = {
     return require('./Libraries/StyleSheet/PlatformColorValueTypesIOS')
       .DynamicColorIOS;
   },
+  // [TODO(macOS ISS#2323203)
   get DynamicColorMacOS(): DynamicColorMacOS {
     return require('./Libraries/StyleSheet/PlatformColorValueTypesMacOS')
       .DynamicColorMacOS;
-  },
+  }, // [TODO(macOS ISS#2323203)
+  // [TODO(macOS GH#750)
+  get ColorWithSystemEffectMacOS(): ColorWithSystemEffectMacOS {
+    return require('./Libraries/StyleSheet/PlatformColorValueTypesMacOS')
+      .ColorWithSystemEffectMacOS;
+  }, // ]TODO(macOS GH#750)
   get ColorAndroid(): ColorAndroid {
     return require('./Libraries/StyleSheet/PlatformColorValueTypesAndroid')
       .ColorAndroid;
diff --git a/local-cli/generator-macos/templates/macos/HelloWorld.xcodeproj/project.pbxproj b/local-cli/generator-macos/templates/macos/HelloWorld.xcodeproj/project.pbxproj
index 54e3200f96b4fc..933b32730bceb2 100644
--- a/local-cli/generator-macos/templates/macos/HelloWorld.xcodeproj/project.pbxproj
+++ b/local-cli/generator-macos/templates/macos/HelloWorld.xcodeproj/project.pbxproj
@@ -465,7 +465,7 @@
 				DEAD_CODE_STRIPPING = NO;
 				INFOPLIST_FILE = "HelloWorld-macos/Info.plist";
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				OTHER_LDFLAGS = (
 					"$(inherited)",
 					"-ObjC",
@@ -485,7 +485,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				INFOPLIST_FILE = "HelloWorld-macos/Info.plist";
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				MACOSX_DEPLOYMENT_TARGET = 10.14;
 				OTHER_LDFLAGS = (
 					"$(inherited)",
 					"-ObjC",
diff --git a/local-cli/generator-macos/templates/macos/Podfile b/local-cli/generator-macos/templates/macos/Podfile
index 44ba1589fed528..b0c122413b3fe3 100644
--- a/local-cli/generator-macos/templates/macos/Podfile
+++ b/local-cli/generator-macos/templates/macos/Podfile
@@ -2,7 +2,7 @@ require_relative '../node_modules/react-native-macos/scripts/react_native_pods'
 require_relative '../node_modules/@react-native-community/cli-platform-ios/native_modules'
 
 target 'HelloWorld-macOS' do
-  platform :macos, '10.13'
+  platform :macos, '10.14'
   use_native_modules!
   use_react_native!(
     :path => '../node_modules/react-native-macos',
diff --git a/scripts/vsto-test-ci.sh b/scripts/vsto-test-ci.sh
index 2843bff8947bd0..8711f77701313b 100755
--- a/scripts/vsto-test-ci.sh
+++ b/scripts/vsto-test-ci.sh
@@ -18,27 +18,27 @@ npm install
 # Setup packager and WebSocket test server
 . ./scripts/vsto-test-setup.sh
 
-# XCode macOS test
+# Xcode macOS test
 xcodebuild -sdk macosx -configuration Debug -project ./RNTester/RNTester.xcodeproj -scheme RNTester-macOS build test DSTROOT=$OUTPUTDIR/macosx/Debug/build.dst OBJROOT=$OUTPUTDIR/macosx/Debug/build.obj SYMROOT=$OUTPUTDIR/macosx/Debug/build.sym SHARED_PRECOMPS_DIR=$OUTPUTDIR/macosx/Debug/build.pch -destination platform=macOS,arch=x86_64 ONLY_ACTIVE_ARCH=NO DEVELOPMENT_TEAM=UBF8T346G9 | /usr/local/bin/xcpretty -r junit --no-color
 
 if [ $? -ne 0 ]; then
-  echo "XCode macOS test FAILED"
+  echo "Xcode macOS test FAILED"
   exit 1
 else
 
-  # XCode iOS test
+  # Xcode iOS test
   xcodebuild -sdk iphonesimulator -configuration Debug -project ./RNTester/RNTester.xcodeproj -scheme RNTester build test DSTROOT=$OUTPUTDIR/iphonesimulator/Debug/build.dst OBJROOT=$OUTPUTDIR/iphonesimulator/Debug/build.obj SYMROOT=$OUTPUTDIR/iphonesimulator/Debug/build.sym SHARED_PRECOMPS_DIR=$OUTPUTDIR/iphonesimulator/Debug/build.pch -destination platform="iOS Simulator,OS=latest,name=iPhone 5s" ONLY_ACTIVE_ARCH=NO DEVELOPMENT_TEAM=UBF8T346G9 | /usr/local/bin/xcpretty -r junit --no-color
 
   if [ $? -ne 0 ]; then
-    echo "XCode iOS test FAILED"
+    echo "Xcode iOS test FAILED"
     exit 1
   else
 
-    # XCode tvOS test
+    # Xcode tvOS test
     xcodebuild -configuration Debug -project ./RNTester/RNTester.xcodeproj -scheme RNTester-tvOS build test DSTROOT=$OUTPUTDIR/iphoneos/Debug/build.dst OBJROOT=$OUTPUTDIR/iphoneos/Debug/build.obj SYMROOT=$OUTPUTDIR/iphoneos/Debug/build.sym SHARED_PRECOMPS_DIR=$OUTPUTDIR/iphoneos/Debug/build.pch -destination platform="tvOS Simulator,OS=latest,name=Apple TV" ONLY_ACTIVE_ARCH=NO DEVELOPMENT_TEAM=UBF8T346G9 | /usr/local/bin/xcpretty -r junit --no-color
 
     if [ $? -ne 0 ]; then
-      echo "XCode tvOS test FAILED"
+      echo "Xcode tvOS test FAILED"
       exit 1
     fi
   fi
diff --git a/scripts/vsto-test-cleanup.sh b/scripts/vsto-test-cleanup.sh
index d249743550a02b..0d8e976893a075 100755
--- a/scripts/vsto-test-cleanup.sh
+++ b/scripts/vsto-test-cleanup.sh
@@ -2,7 +2,7 @@
 set -ex
 
 # Script used by the VSTO build agent to cleanup the packager and web socket server
-# after the XCode test step has completed
+# after the Xcode test step has completed
 
 # kill whatever is occupying port 8081 (packager)
 lsof -i tcp:8081 | awk 'NR!=1 {print $2}' | xargs kill
diff --git a/third-party-podspecs/DoubleConversion.podspec b/third-party-podspecs/DoubleConversion.podspec
index 3a0d0051319d02..24e4f11c9cab54 100644
--- a/third-party-podspecs/DoubleConversion.podspec
+++ b/third-party-podspecs/DoubleConversion.podspec
@@ -19,6 +19,6 @@ Pod::Spec.new do |spec|
   spec.compiler_flags = '-Wno-unreachable-code'
 
   # Pinning to the same version as React.podspec.
-  spec.platforms = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  spec.platforms = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
 
 end
diff --git a/third-party-podspecs/RCT-Folly.podspec b/third-party-podspecs/RCT-Folly.podspec
index 1c4643ac89c9cf..c50bbaa6393b07 100644
--- a/third-party-podspecs/RCT-Folly.podspec
+++ b/third-party-podspecs/RCT-Folly.podspec
@@ -124,5 +124,5 @@ Pod::Spec.new do |spec|
   end
 
   # Pinning to the same version as React.podspec.
-  spec.platforms = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  spec.platforms = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
 end
diff --git a/third-party-podspecs/boost-for-react-native.podspec b/third-party-podspecs/boost-for-react-native.podspec
index fa9be88325021b..b18301127f502c 100644
--- a/third-party-podspecs/boost-for-react-native.podspec
+++ b/third-party-podspecs/boost-for-react-native.podspec
@@ -11,7 +11,7 @@ Pod::Spec.new do |spec|
 
   # Pinning to the same version as React.podspec.
   # TODO: Move this osx addition back upstream to https://github.com/react-native-community/boost-for-react-native
-  spec.platforms = { :ios => '8.0', :tvos => '9.2', :osx => "10.13" }
+  spec.platforms = { :ios => '8.0', :tvos => '9.2', :osx => "10.14" }
   spec.requires_arc = false
 
   spec.module_name = 'boost'
diff --git a/third-party-podspecs/glog.podspec b/third-party-podspecs/glog.podspec
index 6ecaa142bc34fc..be6d96e7b2463d 100644
--- a/third-party-podspecs/glog.podspec
+++ b/third-party-podspecs/glog.podspec
@@ -34,6 +34,6 @@ Pod::Spec.new do |spec|
                                "HEADER_SEARCH_PATHS" => "$(PODS_TARGET_SRCROOT)/src" }
 
   # Pinning to the same version as React.podspec.
-  spec.platforms = { :ios => "10.0", :tvos => "10.0", :osx => "10.13" } # TODO(macOS GH#214)
+  spec.platforms = { :ios => "10.0", :tvos => "10.0", :osx => "10.14" } # TODO(macOS GH#214)
 
 end
diff --git a/third-party-podspecs/libevent.podspec b/third-party-podspecs/libevent.podspec
index 61eb60f919ce41..f8a94ad588e74a 100644
--- a/third-party-podspecs/libevent.podspec
+++ b/third-party-podspecs/libevent.podspec
@@ -544,7 +544,7 @@ Pod::Spec.new do |spec|
   spec.homepage        = "https://libevent.org"
   spec.license         = { :type => "BSD 3-Clause", :file => "LICENSE" }
   spec.author          = "Niels Provos and Nick Mathewson"
-  spec.platforms       = { :osx => "10.13" }
+  spec.platforms       = { :osx => "10.14" }
   spec.source          = { :git => "https://github.com/libevent/libevent.git", :tag => "release-#{spec.version}-stable" }
   spec.default_subspec = "core"
   spec.prepare_command = "touch evconfig-private.h; echo -e #{Shellwords.escape(CONFIG_WITHOUT_OPENSSL)} > include/event2/event-config.h"