diff --git a/packages/react-scripts/bin/react-scripts.js b/packages/react-scripts/bin/react-scripts.js
index 09604f6a03f..59832af1a14 100755
--- a/packages/react-scripts/bin/react-scripts.js
+++ b/packages/react-scripts/bin/react-scripts.js
@@ -8,6 +8,20 @@
 
 'use strict';
 
+// Check Node.js version early for clearer errors (see #5430)
+const currentNodeVersion = process.versions.node;
+const [major] = currentNodeVersion.split('.');
+if (Number(major) < 14) {
+  console.error(
+    'You are running Node ' +
+      currentNodeVersion +
+      '.\n' +
+      'react-scripts requires Node 14 or higher. \n' +
+      'Please update your version of Node.'
+  );
+  process.exit(1);
+}
+
 // Makes the script crash on unhandled rejections instead of silently
 // ignoring them. In the future, promise rejections that are not handled will
 // terminate the Node.js process with a non-zero exit code.
diff --git a/packages/react-scripts/config/modules.js b/packages/react-scripts/config/modules.js
index 22820993a25..1ab4f7ed414 100644
--- a/packages/react-scripts/config/modules.js
+++ b/packages/react-scripts/config/modules.js
@@ -123,7 +123,39 @@ function getModules() {
     // Otherwise we'll check if there is jsconfig.json
     // for non TS projects.
   } else if (hasJsConfig) {
-    config = require(paths.appJsConfig);
+    // Prefer using TypeScript parser to support JSON with comments in jsconfig.json
+    let ts;
+    try {
+      ts = require(
+        resolve.sync('typescript', {
+          basedir: paths.appNodeModules,
+        })
+      );
+    } catch (e) {
+      ts = null;
+    }
+
+    if (ts) {
+      // Use TypeScript's tolerant JSON parser which supports comments (JSONC)
+      config = ts.readConfigFile(paths.appJsConfig, ts.sys.readFile).config;
+    } else {
+      // Fallback: parse as strict JSON and provide actionable error for JSONC
+      try {
+        const fileContent = fs.readFileSync(paths.appJsConfig, 'utf8');
+        config = JSON.parse(fileContent);
+      } catch (e) {
+        throw new Error(
+          chalk.red.bold(
+            'Failed to parse jsconfig.json.\n' +
+              'If your jsconfig.json contains comments, please install TypeScript in your project:\n' +
+              '  npm install --save-dev typescript\n' +
+              'or\n' +
+              '  yarn add --dev typescript\n' +
+              'Create React App will then parse jsconfig.json with comment support.'
+          )
+        );
+      }
+    }
   }
 
   config = config || {};
diff --git a/packages/react-scripts/scripts/eject.js b/packages/react-scripts/scripts/eject.js
index 67e2bb71cde..0addfda6ed4 100644
--- a/packages/react-scripts/scripts/eject.js
+++ b/packages/react-scripts/scripts/eject.js
@@ -237,8 +237,29 @@ prompts({
 
   // Add Babel config
   console.log(`  Adding ${cyan('Babel')} preset`);
+  // Detect if the new JSX transform is available and prefer it after eject
+  const hasJsxRuntime = (() => {
+    if (process.env.DISABLE_NEW_JSX_TRANSFORM === 'true') {
+      return false;
+    }
+    try {
+      require.resolve('react/jsx-runtime');
+      return true;
+    } catch (e) {
+      return false;
+    }
+  })();
+
   appPackage.babel = {
-    presets: ['react-app'],
+    // Preserve preset with explicit runtime so ejected apps keep working without importing React
+    presets: [
+      [
+        'react-app',
+        {
+          runtime: hasJsxRuntime ? 'automatic' : 'classic',
+        },
+      ],
+    ],
   };
 
   // Add ESlint config