diff --git a/.env.example b/.env.example
new file mode 100644
index 00000000..31ff0cfe
--- /dev/null
+++ b/.env.example
@@ -0,0 +1,3 @@
+EXTENSION_ENV=
+EXPERIMENTAL_ERRORS_PLUGIN=
+EXPERIMENTAL_EXTENSION_RESOLVER_PLUGIN=
diff --git a/examples/config-babel/extension.config.js b/examples/config-babel/extension.config.js
index 3e57e763..df6ea986 100644
--- a/examples/config-babel/extension.config.js
+++ b/examples/config-babel/extension.config.js
@@ -1,4 +1,4 @@
-/** @type {import('extension-develop').FileConfig} */
+/** @type {import('extension').FileConfig} */
 module.exports = {
   config: (config) => {
     config.module.rules.push(
diff --git a/examples/content-extension-config/content/ContentApp.tsx b/examples/content-extension-config/content/ContentApp.tsx
index 0fb6dc1a..245ca43e 100644
--- a/examples/content-extension-config/content/ContentApp.tsx
+++ b/examples/content-extension-config/content/ContentApp.tsx
@@ -1,5 +1,5 @@
 import React from 'react'
-import ReactLogo from '../images/logo.svg'
+import reactLogo from '../images/react.png'
 import tailwindBg from '../images/tailwind_bg.png'
 import typescriptLogo from '../images/typescript.png'
 import tailwindLogo from '../images/tailwind.png'
@@ -38,7 +38,11 @@ export default function ContentApp() {
         </div>
         <div className="mx-auto max-w-md text-center lg:py-12 lg:mx-0 lg:flex-auto lg:text-left">
           <div className="flex items-center justify-center space-x-4 my-4 mx-auto">
-            <ReactLogo className="relative inline-block w-12" />
+            <img
+              alt="React logo"
+              src={reactLogo}
+              className="relative inline-block w-12"
+            />
             <div className="text-3xl text-white">+</div>
             <img
               alt="TypeScript logo"
diff --git a/examples/content-extension-config/extension.config.js b/examples/content-extension-config/extension.config.js
index 9c2bf69f..441be9fd 100644
--- a/examples/content-extension-config/extension.config.js
+++ b/examples/content-extension-config/extension.config.js
@@ -1,22 +1,36 @@
-/** @type {import('extension-develop').FileConfig} */
+/** @type {import('extension').FileConfig} */
 module.exports = {
-  config: (config) => {
-    config.module.rules.push(
-      {
-        test: /\.svg$/i,
-        type: 'asset',
-        // *.svg?url
-        resourceQuery: /url/
-      },
-      {
-        test: /\.svg$/i,
-        issuer: /\.[jt]sx?$/,
-        // exclude react component if *.svg?url
-        resourceQuery: {not: [/url/]},
-        use: ['@svgr/webpack']
-      }
-    )
-
-    return config
-  }
+  browsers: {
+    chrome: {
+      // noOpen?: boolean
+      // userDataDir?: string
+      // profile?: string
+      // preferences?: Record<string, any>
+      // browserFlags?: string[]
+      // startingUrl?: string
+      // chromiumBinary?: string
+      startingUrl: 'https://extension.js.org'
+    },
+    firefox: {
+      // noOpen?: boolean
+      // userDataDir?: string
+      // profile?: string
+      // preferences?: Record<string, any>
+      // browserFlags?: string[]
+      // startingUrl?: string
+      // geckoBinary?: string
+      startingUrl: 'about:debugging#/runtime/this-firefox'
+    }
+  },
+  development: {
+    // TBD
+    // browser: DevOptions['browser']
+    // port?: number
+    // browser: 'firefox', // can be an array
+    // zipFilename?: string
+    // zip?: boolean
+    // zipSource?: boolean
+    // polyfill?: boolean
+  },
+  deployment: {}
 }
diff --git a/examples/content-extension-config/images/logo.svg b/examples/content-extension-config/images/logo.svg
deleted file mode 100644
index ea77a618..00000000
--- a/examples/content-extension-config/images/logo.svg
+++ /dev/null
@@ -1,9 +0,0 @@
-<svg xmlns="http://www.w3.org/2000/svg" viewBox="-11.5 -10.23174 23 20.46348">
-  <title>React Logo</title>
-  <circle cx="0" cy="0" r="2.05" fill="#61dafb"/>
-  <g stroke="#61dafb" stroke-width="1" fill="none">
-    <ellipse rx="11" ry="4.2"/>
-    <ellipse rx="11" ry="4.2" transform="rotate(60)"/>
-    <ellipse rx="11" ry="4.2" transform="rotate(120)"/>
-  </g>
-</svg>
diff --git a/examples/content-extension-config/images/react.png b/examples/content-extension-config/images/react.png
new file mode 100644
index 00000000..9080fddd
Binary files /dev/null and b/examples/content-extension-config/images/react.png differ
diff --git a/examples/content-extension-config/package.json b/examples/content-extension-config/package.json
index 2d68c29a..29f0235b 100644
--- a/examples/content-extension-config/package.json
+++ b/examples/content-extension-config/package.json
@@ -15,7 +15,6 @@
     "url": "https://cezaraugusto.com"
   },
   "dependencies": {
-    "@svgr/webpack": "^8.1.0",
     "react": "^18.1.0",
     "react-dom": "^18.1.0",
     "tailwindcss": "^3.4.1"
diff --git a/examples/content-main-world/extension.config.js b/examples/content-main-world/extension.config.js
index 6784b612..f495a447 100644
--- a/examples/content-main-world/extension.config.js
+++ b/examples/content-main-world/extension.config.js
@@ -1,4 +1,4 @@
-/** @type {import('extension-develop').FileConfig} */
+/** @type {import('extension').FileConfig} */
 module.exports = {
   config: (config) => {
     config.output.publicPath =
diff --git a/examples/content-react-svgr/extension.config.js b/examples/content-react-svgr/extension.config.js
index 9c2bf69f..e7d61e2b 100644
--- a/examples/content-react-svgr/extension.config.js
+++ b/examples/content-react-svgr/extension.config.js
@@ -1,4 +1,4 @@
-/** @type {import('extension-develop').FileConfig} */
+/** @type {import('extension').FileConfig} */
 module.exports = {
   config: (config) => {
     config.module.rules.push(
diff --git a/examples/new-crypto/extension.config.js b/examples/new-crypto/extension.config.js
index 701d253b..31eaea22 100644
--- a/examples/new-crypto/extension.config.js
+++ b/examples/new-crypto/extension.config.js
@@ -1,6 +1,6 @@
 const NodePolyfillPlugin = require('node-polyfill-webpack-plugin')
 
-/** @type {import('extension-develop').FileConfig} */
+/** @type {import('extension').FileConfig} */
 module.exports = {
   config: (config) => {
     config.plugins = [
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 43c6c108..bbf4c8a1 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -53,7 +53,7 @@ importers:
         version: 3.3.3
       ts-jest:
         specifier: ^29.1.2
-        version: 29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(jest@29.7.0(@types/node@20.16.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)))(typescript@5.3.3)
+        version: 29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@20.16.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)))(typescript@5.3.3)
       ts-node:
         specifier: ^10.9.2
         version: 10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)
@@ -101,7 +101,7 @@ importers:
         version: 7.25.2
       babel-loader:
         specifier: ^9.1.3
-        version: 9.1.3(@babel/core@7.25.2)(webpack@5.92.1(@swc/core@1.7.26))
+        version: 9.1.3(@babel/core@7.25.2)(webpack@5.92.1(@swc/core@1.7.26)(esbuild@0.23.1))
       babel-preset-modern-browser-extension:
         specifier: ^0.7.0
         version: 0.7.0(@babel/core@7.25.2)
@@ -186,9 +186,6 @@ importers:
 
   examples/content-extension-config:
     dependencies:
-      '@svgr/webpack':
-        specifier: ^8.1.0
-        version: 8.1.0(typescript@5.3.3)
       react:
         specifier: ^18.1.0
         version: 18.3.1
@@ -350,7 +347,7 @@ importers:
     devDependencies:
       node-polyfill-webpack-plugin:
         specifier: ^4.0.0
-        version: 4.0.0(webpack@5.92.1(@swc/core@1.7.26))
+        version: 4.0.0(webpack@5.92.1(@swc/core@1.7.26)(esbuild@0.23.1))
       typescript:
         specifier: 5.3.3
         version: 5.3.3
@@ -547,13 +544,13 @@ importers:
         version: 7.5.8
       jest:
         specifier: ^29.7.0
-        version: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+        version: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       mock-fs:
         specifier: ^5.2.0
         version: 5.2.0
       ts-jest:
         specifier: ^29.1.2
-        version: 29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)))(typescript@5.3.3)
+        version: 29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)))(typescript@5.3.3)
       tsconfig:
         specifier: '*'
         version: 7.0.0
@@ -596,10 +593,10 @@ importers:
         version: 15.9.0
       jest:
         specifier: ^29.7.0
-        version: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+        version: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       ts-jest:
         specifier: ^29.1.2
-        version: 29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)))(typescript@5.3.3)
+        version: 29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)))(typescript@5.3.3)
       tsconfig:
         specifier: '*'
         version: 7.0.0
@@ -814,10 +811,10 @@ importers:
         version: 8.5.12
       jest:
         specifier: ^29.7.0
-        version: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+        version: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       ts-jest:
         specifier: ^29.1.2
-        version: 29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)))(typescript@5.3.3)
+        version: 29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)))(typescript@5.3.3)
       tsup:
         specifier: ^8.0.1
         version: 8.2.4(@swc/core@1.7.26)(jiti@1.21.6)(postcss@8.4.47)(typescript@5.3.3)(yaml@2.5.1)
@@ -8144,41 +8141,6 @@ snapshots:
       - supports-color
       - ts-node
 
-  '@jest/core@29.7.0(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))':
-    dependencies:
-      '@jest/console': 29.7.0
-      '@jest/reporters': 29.7.0
-      '@jest/test-result': 29.7.0
-      '@jest/transform': 29.7.0
-      '@jest/types': 29.6.3
-      '@types/node': 20.16.5
-      ansi-escapes: 4.3.2
-      chalk: 4.1.2
-      ci-info: 3.9.0
-      exit: 0.1.2
-      graceful-fs: 4.2.11
-      jest-changed-files: 29.7.0
-      jest-config: 29.7.0(@types/node@20.16.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
-      jest-haste-map: 29.7.0
-      jest-message-util: 29.7.0
-      jest-regex-util: 29.6.3
-      jest-resolve: 29.7.0
-      jest-resolve-dependencies: 29.7.0
-      jest-runner: 29.7.0
-      jest-runtime: 29.7.0
-      jest-snapshot: 29.7.0
-      jest-util: 29.7.0
-      jest-validate: 29.7.0
-      jest-watcher: 29.7.0
-      micromatch: 4.0.8
-      pretty-format: 29.7.0
-      slash: 3.0.0
-      strip-ansi: 6.0.1
-    transitivePeerDependencies:
-      - babel-plugin-macros
-      - supports-color
-      - ts-node
-
   '@jest/environment@29.7.0':
     dependencies:
       '@jest/fake-timers': 29.7.0
@@ -9356,14 +9318,6 @@ snapshots:
       find-cache-dir: 4.0.0
       schema-utils: 4.2.0
       webpack: 5.92.1(@swc/core@1.7.26)(esbuild@0.23.1)
-    optional: true
-
-  babel-loader@9.1.3(@babel/core@7.25.2)(webpack@5.92.1(@swc/core@1.7.26)):
-    dependencies:
-      '@babel/core': 7.25.2
-      find-cache-dir: 4.0.0
-      schema-utils: 4.2.0
-      webpack: 5.92.1(@swc/core@1.7.26)
 
   babel-plugin-istanbul@6.1.1:
     dependencies:
@@ -9823,13 +9777,13 @@ snapshots:
       - supports-color
       - ts-node
 
-  create-jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)):
+  create-jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)):
     dependencies:
       '@jest/types': 29.6.3
       chalk: 4.1.2
       exit: 0.1.2
       graceful-fs: 4.2.11
-      jest-config: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+      jest-config: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       jest-util: 29.7.0
       prompts: 2.4.2
     transitivePeerDependencies:
@@ -10988,16 +10942,16 @@ snapshots:
       - supports-color
       - ts-node
 
-  jest-cli@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)):
+  jest-cli@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)):
     dependencies:
-      '@jest/core': 29.7.0(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+      '@jest/core': 29.7.0(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       '@jest/test-result': 29.7.0
       '@jest/types': 29.6.3
       chalk: 4.1.2
-      create-jest: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+      create-jest: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       exit: 0.1.2
       import-local: 3.2.0
-      jest-config: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+      jest-config: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       jest-util: 29.7.0
       jest-validate: 29.7.0
       yargs: 17.7.2
@@ -11038,38 +10992,7 @@ snapshots:
       - babel-plugin-macros
       - supports-color
 
-  jest-config@29.7.0(@types/node@20.16.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)):
-    dependencies:
-      '@babel/core': 7.25.2
-      '@jest/test-sequencer': 29.7.0
-      '@jest/types': 29.6.3
-      babel-jest: 29.7.0(@babel/core@7.25.2)
-      chalk: 4.1.2
-      ci-info: 3.9.0
-      deepmerge: 4.3.1
-      glob: 7.2.3
-      graceful-fs: 4.2.11
-      jest-circus: 29.7.0
-      jest-environment-node: 29.7.0
-      jest-get-type: 29.6.3
-      jest-regex-util: 29.6.3
-      jest-resolve: 29.7.0
-      jest-runner: 29.7.0
-      jest-util: 29.7.0
-      jest-validate: 29.7.0
-      micromatch: 4.0.8
-      parse-json: 5.2.0
-      pretty-format: 29.7.0
-      slash: 3.0.0
-      strip-json-comments: 3.1.1
-    optionalDependencies:
-      '@types/node': 20.16.5
-      ts-node: 10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)
-    transitivePeerDependencies:
-      - babel-plugin-macros
-      - supports-color
-
-  jest-config@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)):
+  jest-config@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)):
     dependencies:
       '@babel/core': 7.25.2
       '@jest/test-sequencer': 29.7.0
@@ -11095,7 +11018,7 @@ snapshots:
       strip-json-comments: 3.1.1
     optionalDependencies:
       '@types/node': 22.5.5
-      ts-node: 10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)
+      ts-node: 10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)
     transitivePeerDependencies:
       - babel-plugin-macros
       - supports-color
@@ -11333,12 +11256,12 @@ snapshots:
       - supports-color
       - ts-node
 
-  jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)):
+  jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)):
     dependencies:
-      '@jest/core': 29.7.0(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+      '@jest/core': 29.7.0(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       '@jest/types': 29.6.3
       import-local: 3.2.0
-      jest-cli: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+      jest-cli: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
     transitivePeerDependencies:
       - '@types/node'
       - babel-plugin-macros
@@ -11653,7 +11576,7 @@ snapshots:
 
   node-int64@0.4.0: {}
 
-  node-polyfill-webpack-plugin@4.0.0(webpack@5.92.1(@swc/core@1.7.26)):
+  node-polyfill-webpack-plugin@4.0.0(webpack@5.92.1(@swc/core@1.7.26)(esbuild@0.23.1)):
     dependencies:
       assert: 2.1.0
       browserify-zlib: 0.2.0
@@ -11679,7 +11602,7 @@ snapshots:
       url: 0.11.4
       util: 0.12.5
       vm-browserify: 1.1.2
-      webpack: 5.92.1(@swc/core@1.7.26)
+      webpack: 5.92.1(@swc/core@1.7.26)(esbuild@0.23.1)
 
   node-releases@2.0.18: {}
 
@@ -13022,17 +12945,6 @@ snapshots:
       '@swc/core': 1.7.26
       esbuild: 0.23.1
 
-  terser-webpack-plugin@5.3.10(@swc/core@1.7.26)(webpack@5.92.1(@swc/core@1.7.26)):
-    dependencies:
-      '@jridgewell/trace-mapping': 0.3.25
-      jest-worker: 27.5.1
-      schema-utils: 3.3.0
-      serialize-javascript: 6.0.2
-      terser: 5.32.0
-      webpack: 5.92.1(@swc/core@1.7.26)
-    optionalDependencies:
-      '@swc/core': 1.7.26
-
   terser@5.32.0:
     dependencies:
       '@jridgewell/source-map': 0.3.6
@@ -13107,12 +13019,12 @@ snapshots:
 
   ts-interface-checker@0.1.13: {}
 
-  ts-jest@29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3)))(typescript@5.3.3):
+  ts-jest@29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@20.16.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)))(typescript@5.3.3):
     dependencies:
       bs-logger: 0.2.6
       ejs: 3.1.10
       fast-json-stable-stringify: 2.1.0
-      jest: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@22.5.5)(typescript@5.3.3))
+      jest: 29.7.0(@types/node@20.16.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       jest-util: 29.7.0
       json5: 2.2.3
       lodash.memoize: 4.1.2
@@ -13127,12 +13039,12 @@ snapshots:
       babel-jest: 29.7.0(@babel/core@7.25.2)
       esbuild: 0.23.1
 
-  ts-jest@29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(jest@29.7.0(@types/node@20.16.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)))(typescript@5.3.3):
+  ts-jest@29.2.5(@babel/core@7.25.2)(@jest/transform@29.7.0)(@jest/types@29.6.3)(babel-jest@29.7.0(@babel/core@7.25.2))(esbuild@0.23.1)(jest@29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3)))(typescript@5.3.3):
     dependencies:
       bs-logger: 0.2.6
       ejs: 3.1.10
       fast-json-stable-stringify: 2.1.0
-      jest: 29.7.0(@types/node@20.16.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
+      jest: 29.7.0(@types/node@22.5.5)(ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3))
       jest-util: 29.7.0
       json5: 2.2.3
       lodash.memoize: 4.1.2
@@ -13145,6 +13057,7 @@ snapshots:
       '@jest/transform': 29.7.0
       '@jest/types': 29.6.3
       babel-jest: 29.7.0(@babel/core@7.25.2)
+      esbuild: 0.23.1
 
   ts-node@10.9.2(@swc/core@1.7.26)(@types/node@20.16.5)(typescript@5.3.3):
     dependencies:
@@ -13466,37 +13379,6 @@ snapshots:
     dependencies:
       webpack: 5.92.1(@swc/core@1.7.26)(esbuild@0.23.1)
 
-  webpack@5.92.1(@swc/core@1.7.26):
-    dependencies:
-      '@types/eslint-scope': 3.7.7
-      '@types/estree': 1.0.5
-      '@webassemblyjs/ast': 1.12.1
-      '@webassemblyjs/wasm-edit': 1.12.1
-      '@webassemblyjs/wasm-parser': 1.12.1
-      acorn: 8.12.1
-      acorn-import-attributes: 1.9.5(acorn@8.12.1)
-      browserslist: 4.23.3
-      chrome-trace-event: 1.0.4
-      enhanced-resolve: 5.17.1
-      es-module-lexer: 1.5.4
-      eslint-scope: 5.1.1
-      events: 3.3.0
-      glob-to-regexp: 0.4.1
-      graceful-fs: 4.2.11
-      json-parse-even-better-errors: 2.3.1
-      loader-runner: 4.3.0
-      mime-types: 2.1.35
-      neo-async: 2.6.2
-      schema-utils: 3.3.0
-      tapable: 2.2.1
-      terser-webpack-plugin: 5.3.10(@swc/core@1.7.26)(webpack@5.92.1(@swc/core@1.7.26))
-      watchpack: 2.4.2
-      webpack-sources: 3.2.3
-    transitivePeerDependencies:
-      - '@swc/core'
-      - esbuild
-      - uglify-js
-
   webpack@5.92.1(@swc/core@1.7.26)(esbuild@0.23.1):
     dependencies:
       '@types/eslint-scope': 3.7.7
diff --git a/programs/cli/cli.ts b/programs/cli/cli.ts
index ab99ec96..4762dc5c 100755
--- a/programs/cli/cli.ts
+++ b/programs/cli/cli.ts
@@ -15,14 +15,17 @@ import {
   extensionStart,
   type StartOptions,
   extensionBuild,
-  type BuildOptions
-  // extensionPreview
+  type BuildOptions,
+  // extensionPreview,
+  type FileConfig
 } from 'extension-develop'
 import * as messages from './cli-lib/messages'
 import type {BrowsersSupported} from './types'
 import checkUpdates from './check-updates'
 import packageJson from './package.json'
 
+export {type FileConfig}
+
 // Before all, check for updates.
 checkUpdates(packageJson)
 
diff --git a/programs/develop/commands/commands-lib/config-types.ts b/programs/develop/commands/commands-lib/config-types.ts
index 41b53771..fd616335 100644
--- a/programs/develop/commands/commands-lib/config-types.ts
+++ b/programs/develop/commands/commands-lib/config-types.ts
@@ -1,5 +1,13 @@
 import {Configuration} from 'webpack'
+import {DevOptions} from '../dev'
+import {StartOptions} from '../start'
+import {PreviewOptions} from '../preview'
+import {BuildOptions} from '../build'
 
 export interface FileConfig {
+  dev: DevOptions
+  start: StartOptions
+  preview: PreviewOptions
+  build: BuildOptions
   config: (config: Configuration) => Configuration
 }
diff --git a/programs/develop/commands/commands-lib/get-extension-config.ts b/programs/develop/commands/commands-lib/get-extension-config.ts
index 168aaff7..d28a26c4 100644
--- a/programs/develop/commands/commands-lib/get-extension-config.ts
+++ b/programs/develop/commands/commands-lib/get-extension-config.ts
@@ -2,6 +2,7 @@ import fs from 'fs'
 import path from 'path'
 import {Configuration} from 'webpack'
 import {FileConfig} from './config-types'
+import {DevOptions} from '../../commands/dev'
 import * as messages from './messages'
 
 export function loadExtensionConfig(projectPath: string) {
@@ -21,10 +22,51 @@ export function loadExtensionConfig(projectPath: string) {
   return (config: Configuration) => config
 }
 
+export function loadCommandConfig(
+  projectPath: string,
+  command: 'dev' | 'build' | 'start' | 'preview'
+) {
+  const userConfigPath = path.join(projectPath, 'extension.config.js')
+
+  if (fs.existsSync(userConfigPath)) {
+    if (isUsingExtensionConfig(projectPath)) {
+      const userConfig: any = require(userConfigPath)
+      if (userConfig && userConfig != null) {
+        return userConfig![command]
+      }
+    }
+  }
+
+  return {}
+}
+
+export function loadBrowserConfig(
+  projectPath: string,
+  browser: DevOptions['browser']
+) {
+  const userConfigPath = path.join(projectPath, 'extension.config.js')
+
+  if (fs.existsSync(userConfigPath)) {
+    if (isUsingExtensionConfig(projectPath)) {
+      const userConfig: any = require(userConfigPath)
+      if (userConfig && userConfig != null) {
+        return userConfig.browsers![browser]
+      }
+    }
+  }
+
+  return {}
+}
+
+let userMessageDelivered = false
+
 export function isUsingExtensionConfig(projectPath: string) {
   const configPath = path.join(projectPath, 'extension.config.js')
   if (fs.existsSync(configPath)) {
-    console.log(messages.isUsingExtensionConfig('extension.config.js'))
+    if (!userMessageDelivered) {
+      console.log(messages.isUsingExtensionConfig('extension.config.js'))
+      userMessageDelivered = true
+    }
     return true
   } else {
     return false
diff --git a/programs/develop/plugin-browsers/index.ts b/programs/develop/plugin-browsers/index.ts
index 22182b7d..e4572799 100644
--- a/programs/develop/plugin-browsers/index.ts
+++ b/programs/develop/plugin-browsers/index.ts
@@ -5,6 +5,7 @@ import {type PluginInterface} from './browsers-types'
 import {RunChromiumPlugin} from './run-chromium'
 import {RunFirefoxPlugin} from './run-firefox'
 import {DevOptions} from '../commands/dev'
+import {loadBrowserConfig} from '../commands/commands-lib/get-extension-config'
 
 /**
  * BrowsersPlugin works by finding the binary for the browser specified in the
@@ -84,27 +85,32 @@ export class BrowsersPlugin {
         this.browser,
         this.userDataDir || this.profile
       ),
+      startingUrl: this.startingUrl,
       chromiumBinary: this.chromiumBinary,
       geckoBinary: this.geckoBinary
     }
 
-    console.log('browser', this.browser)
+    const browserConfig = {
+      ...config,
+      ...loadBrowserConfig(compiler.context, this.browser)
+    }
+
     switch (this.browser) {
       case 'chrome':
       case 'edge':
       case 'chromium-based': {
-        new RunChromiumPlugin(config).apply(compiler)
+        new RunChromiumPlugin(browserConfig).apply(compiler)
         break
       }
 
       case 'firefox':
       case 'gecko-based':
-        new RunFirefoxPlugin(config).apply(compiler)
+        new RunFirefoxPlugin(browserConfig).apply(compiler)
         break
 
       default: {
         new RunChromiumPlugin({
-          ...config,
+          ...browserConfig,
           browser: 'chrome'
         }).apply(compiler)
         break
diff --git a/programs/develop/plugin-browsers/run-chromium/browser-config.ts b/programs/develop/plugin-browsers/run-chromium/browser-config.ts
index 666ebf9e..2b3b5ab7 100644
--- a/programs/develop/plugin-browsers/run-chromium/browser-config.ts
+++ b/programs/develop/plugin-browsers/run-chromium/browser-config.ts
@@ -9,7 +9,7 @@ export function browserConfig(configOptions: PluginInterface) {
   const userProfilePath = createProfile(
     configOptions.browser,
     configOptions.profile,
-    false
+    configOptions.preferences
   )
 
   // Flags set by default:
diff --git a/programs/develop/plugin-browsers/run-chromium/create-profile.ts b/programs/develop/plugin-browsers/run-chromium/create-profile.ts
index 82377023..c6ee18ee 100644
--- a/programs/develop/plugin-browsers/run-chromium/create-profile.ts
+++ b/programs/develop/plugin-browsers/run-chromium/create-profile.ts
@@ -10,8 +10,8 @@ import {DevOptions} from '../../commands/dev'
 
 export function createProfile(
   browser: DevOptions['browser'],
-  profilePath?: string,
-  silent?: boolean
+  profilePath: string | undefined,
+  configPreferences: DevOptions['preferences']
 ) {
   if (profilePath && fs.existsSync(profilePath)) {
     return profilePath
@@ -24,22 +24,20 @@ export function createProfile(
   const preferences =
     browser === 'chrome' ? chromeMasterPreferences : edgeMasterPreferences
 
-  const userProfile = JSON.stringify(preferences)
+  const userProfile = JSON.stringify({...preferences, ...configPreferences})
 
-  if (!silent) {
-    addProgressBar(messages.creatingUserProfile(browser), () => {
-      const profilePath = path.resolve(__dirname, `run-${browser}-profile`)
-      const preferences = path.join(profilePath, 'Default')
+  addProgressBar(messages.creatingUserProfile(browser), () => {
+    const profilePath = path.resolve(__dirname, `run-${browser}-profile`)
+    const preferences = path.join(profilePath, 'Default')
 
-      // Ensure directory exists
-      fs.mkdirSync(preferences, {recursive: true})
+    // Ensure directory exists
+    fs.mkdirSync(preferences, {recursive: true})
 
-      const preferencesPath = path.join(preferences, 'Preferences')
+    const preferencesPath = path.join(preferences, 'Preferences')
 
-      // Actually write the user preferences
-      fs.writeFileSync(preferencesPath, userProfile, 'utf8')
-    })
-  }
+    // Actually write the user preferences
+    fs.writeFileSync(preferencesPath, userProfile, 'utf8')
+  })
 
   return path.resolve(__dirname, `run-${browser}-profile`)
 }
diff --git a/programs/develop/plugin-browsers/run-chromium/index.ts b/programs/develop/plugin-browsers/run-chromium/index.ts
index a6e4bea8..5fd8216e 100644
--- a/programs/develop/plugin-browsers/run-chromium/index.ts
+++ b/programs/develop/plugin-browsers/run-chromium/index.ts
@@ -67,6 +67,7 @@ export class RunChromiumPlugin {
     }
 
     const chromiumConfig = browserConfig(this)
+    console.log('asdlasdlasdaldjsalds', this.startingUrl)
     const launchArgs = this.startingUrl
       ? [this.startingUrl, ...chromiumConfig]
       : [...chromiumConfig]
diff --git a/programs/develop/plugin-browsers/run-firefox/firefox/browser-config.ts b/programs/develop/plugin-browsers/run-firefox/firefox/browser-config.ts
index 36910fff..f13c5ea2 100644
--- a/programs/develop/plugin-browsers/run-firefox/firefox/browser-config.ts
+++ b/programs/develop/plugin-browsers/run-firefox/firefox/browser-config.ts
@@ -1,29 +1,24 @@
 import {Compiler} from 'webpack'
 import {createUserDataDir} from './create-profile'
-import {type PluginInterface} from '../../browsers-types'
+import {type DevOptions} from '../../../commands/dev'
 
 export async function browserConfig(
   compiler: Compiler,
-  configOptions: PluginInterface
+  configOptions: DevOptions
 ) {
   const {
     browser,
     startingUrl,
     preferences,
     userDataDir,
-    browserConsole = false,
     browserFlags = []
   } = configOptions
 
-  const profile = createUserDataDir(browser, userDataDir, preferences)
+  const userProfilePath = createUserDataDir(browser, userDataDir, preferences)
   const binaryArgs: string[] = []
 
   if (startingUrl) {
-    binaryArgs.push(`--url "${startingUrl}"`)
-  }
-
-  if (browserConsole) {
-    binaryArgs.push('--jsconsole')
+    binaryArgs.push(`--url=${startingUrl}`)
   }
 
   if (browserFlags) {
@@ -35,9 +30,9 @@ export async function browserConfig(
     : 9222
 
   return [
-    `--binary-args "${browserFlags.join(' ')}"`,
-    `--profile "${profile.path()}"`,
-    `--listen ${port}`,
+    `--binary-args="${binaryArgs.join(' ')}"`,
+    `--profile="${userProfilePath.path()}"`,
+    `--listen=${port}`,
     '--verbose'
   ].join(' ')
 }
diff --git a/programs/develop/plugin-browsers/run-firefox/firefox/create-profile.ts b/programs/develop/plugin-browsers/run-firefox/firefox/create-profile.ts
index 1882d839..9b0b72ab 100644
--- a/programs/develop/plugin-browsers/run-firefox/firefox/create-profile.ts
+++ b/programs/develop/plugin-browsers/run-firefox/firefox/create-profile.ts
@@ -5,16 +5,24 @@ import {getPreferences} from './master-preferences'
 import * as messages from '../../browsers-lib/messages'
 import {addProgressBar} from '../../browsers-lib/add-progress-bar'
 import {DevOptions} from '../../../commands/dev'
+import {loadBrowserConfig} from '../../../commands/commands-lib/get-extension-config'
 
 function configureProfile(
   profile: FirefoxProfile,
   customPreferences: Record<string, any>
 ) {
-  const preferences: Record<string, any> = getPreferences(customPreferences)
-  const preferenceKeys = Object.keys(preferences)
+  const firefoxMasterPreferences: Record<string, any> = {
+    ...loadBrowserConfig(path.resolve(__dirname, 'run-firefox'), 'firefox'),
+    ...getPreferences(customPreferences)
+  }
+
+  const preferenceKeys = Object.keys(firefoxMasterPreferences)
 
   preferenceKeys.forEach((preference) => {
-    profile.setPreference(preference, preferences[preference] as string)
+    profile.setPreference(
+      preference,
+      firefoxMasterPreferences[preference] as string
+    )
   })
 
   const customPreferenceKeys = Object.keys(customPreferences)
@@ -36,7 +44,7 @@ function createProfile(
 ) {
   const profile = new FirefoxProfile({destinationDirectory})
   const profileConfigured = configureProfile(profile, customPreferences)
-
+  console.log({profileConfigured})
   return profileConfigured
 }
 
@@ -64,21 +72,25 @@ function getProfile(
 export function createUserDataDir(
   browser: DevOptions['browser'],
   dataDirPath: string | undefined,
-  preferences?: Record<string, any>,
-  silent?: boolean
+  configPreferences: DevOptions['preferences']
 ) {
   let profile: FirefoxProfile
   const dataDir = dataDirPath || path.resolve(__dirname, 'run-firefox-data-dir')
+  const firefoxMasterPreferences: Record<string, any> = getPreferences(
+    configPreferences || {}
+  )
+
+  const preferences = firefoxMasterPreferences
+
+  const userPreferences = {...preferences, ...configPreferences}
 
   if (fs.existsSync(dataDir)) {
-    profile = getProfile(browser, dataDir, preferences || {})
+    profile = getProfile(browser, dataDir, userPreferences)
   } else {
-    if (!silent) {
-      addProgressBar(messages.creatingUserProfile(browser), () => {})
-    }
+    addProgressBar(messages.creatingUserProfile(browser), () => {})
 
     fs.mkdirSync(dataDir, {recursive: true})
-    profile = createProfile(dataDir, preferences || {})
+    profile = createProfile(dataDir, userPreferences)
   }
 
   return profile
diff --git a/programs/develop/plugin-browsers/run-firefox/index.ts b/programs/develop/plugin-browsers/run-firefox/index.ts
index 7bed62e5..6e4a5037 100644
--- a/programs/develop/plugin-browsers/run-firefox/index.ts
+++ b/programs/develop/plugin-browsers/run-firefox/index.ts
@@ -71,15 +71,12 @@ export class RunFirefoxPlugin {
     }
   }
 
-  private async launchFirefox(
-    compiler: Compiler,
-    browser: DevOptions['browser']
-  ) {
+  private async launchFirefox(compiler: Compiler, options: DevOptions) {
     const fxRunnerCmd = await this.getFxRunnerCommand()
 
     let browserBinaryLocation: string
 
-    switch (browser) {
+    switch (options.browser) {
       case 'gecko-based':
         browserBinaryLocation = path.normalize(this.geckoBinary!)
         break
@@ -101,7 +98,7 @@ export class RunFirefoxPlugin {
       process.exit(1)
     }
 
-    const firefoxConfig = await browserConfig(compiler, this)
+    const firefoxConfig = await browserConfig(compiler, options)
     const cmd = `${firefoxLaunchPath} ${firefoxConfig}`
 
     child = exec(cmd, (error, _stdout, stderr) => {
@@ -161,7 +158,15 @@ export class RunFirefoxPlugin {
           )
         }, 2000)
 
-        await this.launchFirefox(compiler, this.browser)
+        await this.launchFirefox(compiler, {
+          browser: this.browser,
+          browserFlags: this.browserFlags,
+          userDataDir: this.userDataDir,
+          profile: this.profile,
+          preferences: this.preferences,
+          startingUrl: this.startingUrl,
+          mode: compilation.compilation.options.mode
+        })
 
         firefoxDidLaunch = true
         done()
diff --git a/programs/develop/webpack/dev-server.ts b/programs/develop/webpack/dev-server.ts
index b0e01ca3..0c57a563 100644
--- a/programs/develop/webpack/dev-server.ts
+++ b/programs/develop/webpack/dev-server.ts
@@ -12,7 +12,10 @@ import {merge} from 'webpack-merge'
 import webpackConfig from './webpack-config'
 import type {DevOptions} from '../commands/dev'
 import * as utils from './lib/utils'
-import {loadExtensionConfig} from '../commands/commands-lib/get-extension-config'
+import {
+  loadCommandConfig,
+  loadExtensionConfig
+} from '../commands/commands-lib/get-extension-config'
 
 function closeAll(devServer: WebpackDevServer) {
   devServer
@@ -29,8 +32,10 @@ export async function devServer(
   projectPath: string,
   {...devOptions}: DevOptions
 ) {
+  const commandConfig = loadCommandConfig(projectPath, 'dev')
   const baseConfig = webpackConfig(projectPath, {
     ...devOptions,
+    ...commandConfig,
     mode: 'development'
   })
   const userExtensionConfig = loadExtensionConfig(projectPath)
diff --git a/programs/develop/webpack/lib/messages.ts b/programs/develop/webpack/lib/messages.ts
index 10d69ea5..be4b21bd 100644
--- a/programs/develop/webpack/lib/messages.ts
+++ b/programs/develop/webpack/lib/messages.ts
@@ -30,7 +30,7 @@ function getLoggingPrefix(feature: string, type: PrefixType): string {
 
   const arrow = type === 'info' ? cyan('►►►') : brightGreen('►►►')
 
-  return `${arrow} ${feature}`
+  return `${arrow} ${cyan(feature)}`
 }
 
 export function capitalizedBrowserName(browser: DevOptions['browser']) {
diff --git a/programs/develop/webpack/plugin-extension/index.ts b/programs/develop/webpack/plugin-extension/index.ts
index 338d12a7..fc625e04 100644
--- a/programs/develop/webpack/plugin-extension/index.ts
+++ b/programs/develop/webpack/plugin-extension/index.ts
@@ -45,7 +45,7 @@ export class ExtensionPlugin {
     const manifestFieldsData = getManifestFieldsData({manifestPath})
     const specialFoldersData = getSpecialFoldersData({manifestPath})
 
-    process.env.EXTENSION_ENV === 'development' &&
+    process.env.EXPERIMENTAL_EXTENSION_RESOLVER_PLUGIN &&
       new ResolvePlugin({
         manifestPath,
         includeList: {
diff --git a/programs/develop/webpack/webpack-config.ts b/programs/develop/webpack/webpack-config.ts
index 57b97bdc..163a789e 100644
--- a/programs/develop/webpack/webpack-config.ts
+++ b/programs/develop/webpack/webpack-config.ts
@@ -102,7 +102,7 @@ export default function webpackConfig(
       new JsFrameworksPlugin({
         manifestPath
       }),
-      process.env.EXTENSION_ENV === 'development' &&
+      process.env.EXPERIMENTAL_ERRORS_PLUGIN &&
         new ErrorsPlugin({
           manifestPath,
           browser