diff --git a/code/addons/themes/package.json b/code/addons/themes/package.json
index 1d5a3857a9f8..5e690f76608e 100644
--- a/code/addons/themes/package.json
+++ b/code/addons/themes/package.json
@@ -43,7 +43,8 @@
       "require": "./dist/preview.js",
       "import": "./dist/preview.mjs"
     },
-    "./package.json": "./package.json"
+    "./package.json": "./package.json",
+    "./postinstall": "./postinstall.js"
   },
   "main": "dist/index.js",
   "module": "dist/index.mjs",
diff --git a/code/addons/themes/postinstall.js b/code/addons/themes/postinstall.js
new file mode 100644
index 000000000000..c84a4e88e4b4
--- /dev/null
+++ b/code/addons/themes/postinstall.js
@@ -0,0 +1,17 @@
+const { spawn } = require('child_process');
+
+const PACKAGE_MANAGER_TO_COMMAND = {
+  npm: 'npx',
+  yarn1: 'yarn dlx',
+  yarn2: 'yarn dlx',
+  pnpm: 'pnpm dlx',
+};
+
+module.exports = function postinstall(options) {
+  const command = PACKAGE_MANAGER_TO_COMMAND[options.packageManager];
+
+  spawn(command, ['@storybook/auto-config', 'themes'], {
+    stdio: 'inherit',
+    cwd: process.cwd(),
+  });
+};
diff --git a/code/lib/cli/src/add.ts b/code/lib/cli/src/add.ts
index 2b8565085dab..c5ddd1b1c995 100644
--- a/code/lib/cli/src/add.ts
+++ b/code/lib/cli/src/add.ts
@@ -1,5 +1,6 @@
 import { getStorybookInfo } from '@storybook/core-common';
 import { readConfig, writeConfig } from '@storybook/csf-tools';
+import SemVer from 'semver';
 
 import {
   JsPackageManagerFactory,
@@ -10,7 +11,11 @@ import { getStorybookVersion } from './utils';
 
 const logger = console;
 
-const postinstallAddon = async (addonName: string) => {
+interface PostinstallOptions {
+  packageManager: PackageManagerName;
+}
+
+const postinstallAddon = async (addonName: string, options: PostinstallOptions) => {
   try {
     const modulePath = require.resolve(`${addonName}/postinstall`, { paths: [process.cwd()] });
     // eslint-disable-next-line import/no-dynamic-require, global-require
@@ -18,7 +23,7 @@ const postinstallAddon = async (addonName: string) => {
 
     try {
       logger.log(`Running postinstall script for ${addonName}`);
-      await postinstall();
+      await postinstall(options);
     } catch (e) {
       logger.error(`Error running postinstall script for ${addonName}`);
       logger.error(e);
@@ -73,7 +78,9 @@ export async function add(
   const isStorybookAddon = addonName.startsWith('@storybook/');
   const storybookVersion = await getStorybookVersion(packageManager);
   const version = versionSpecifier || (isStorybookAddon ? storybookVersion : latestVersion);
-  const addonWithVersion = `${addonName}@^${version}`;
+  const addonWithVersion = SemVer.valid(version)
+    ? `${addonName}@^${version}`
+    : `${addonName}@${version}`;
   logger.log(`Installing ${addonWithVersion}`);
   await packageManager.addDependencies({ installAsDevDependencies: true }, [addonWithVersion]);
 
@@ -83,6 +90,6 @@ export async function add(
   await writeConfig(main);
 
   if (!options.skipPostinstall && isStorybookAddon) {
-    await postinstallAddon(addonName);
+    await postinstallAddon(addonName, { packageManager: pkgMgr });
   }
 }