Fix crash attempting to get runtime when shutting down instance

.ado/jobs/linting.yml

@@ -48,11 +48,12 @@ jobs:
       - script: yarn lint
         displayName: yarn lint
 
-      - script: yarn validate-overrides
-        displayName: yarn validate-overrides
-        ${{ if eq(parameters.buildEnvironment, 'Continuous') }}:
-          env:
-            PLATFORM_OVERRIDE_GITHUB_TOKEN: $(GitHubOAuthToken)
+      # Disable while facebook/react-native -> react/react-native migration breaks CI
+      # - script: yarn validate-overrides
+      #  displayName: yarn validate-overrides
+      #  ${{ if eq(parameters.buildEnvironment, 'Continuous') }}:
+      #    env:
+      #      PLATFORM_OVERRIDE_GITHUB_TOKEN: $(GitHubOAuthToken)
 
       - script: npx unbroken -q --local-only --allow-local-line-sections
         displayName: check local links in .md files

.ado/jobs/macos-tests.yml

@@ -18,5 +18,6 @@ jobs:
       - script: yarn test
         displayName: yarn test
 
-      - script: yarn validate-overrides
-        displayName: yarn validate-overrides
+      # Disable while facebook/react-native -> react/react-native migration breaks CI
+      # - script: yarn validate-overrides
+      #  displayName: yarn validate-overrides

change/react-native-windows-7a98fbf7-0186-4130-b6ab-409caa188bee.json

@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "Fix crash attempting to get runtime when shutting down instance",
+  "packageName": "react-native-windows",
+  "email": "30809111+acoates-ms@users.noreply.github.com",
+  "dependentChangeType": "patch"
+}

vnext/Microsoft.ReactNative.Cxx/NativeModules.h

@@ -527,7 +527,8 @@ struct ModuleJsiInitMethodInfo<void (TModule::*)(ReactContext const &, facebook:
     return
         [module = static_cast<ModuleType *>(module), method](
             ReactContext const &reactContext, winrt::Windows::Foundation::IInspectable const &runtimeHandle) noexcept {
-          (module->*method)(reactContext, GetOrCreateContextRuntime(reactContext, runtimeHandle));
+          if (runtimeHandle)
+            (module->*method)(reactContext, GetOrCreateContextRuntime(reactContext, runtimeHandle));
         };
   }
 };