diff --git a/extension/src/browser/extension/inject/deprecatedWarn.ts b/extension/src/browser/extension/inject/deprecatedWarn.ts
deleted file mode 100644
index e2dbc190..00000000
--- a/extension/src/browser/extension/inject/deprecatedWarn.ts
+++ /dev/null
@@ -1,7 +0,0 @@
-// Deprecated warning for inject.bundle.js
-/* eslint-disable no-console */
-console.warn(
-  "Using Redux DevTools inside extensions is deprecated and won't be supported in the next major version. " +
-    'Please use https://github.com/zalmoxisus/remote-redux-devtools instead.'
-);
-/* eslint-enable no-console */
diff --git a/extension/src/browser/extension/inject/index.ts b/extension/src/browser/extension/inject/index.ts
deleted file mode 100644
index dfb369b7..00000000
--- a/extension/src/browser/extension/inject/index.ts
+++ /dev/null
@@ -1,22 +0,0 @@
-// Include this script in Chrome apps and extensions for remote debugging
-// <script src="chrome-extension://lmhkpmbekcpmknklioeibfkpmmfibljd/js/redux-devtools-extension.bundle.js"></script>
-
-import { Options } from '../options/syncOptions';
-
-window.devToolsExtensionID = 'lmhkpmbekcpmknklioeibfkpmmfibljd';
-require('./contentScript');
-require('./pageScript');
-
-chrome.runtime.sendMessage(
-  window.devToolsExtensionID,
-  { type: 'GET_OPTIONS' },
-  function (response: { readonly options: Options }) {
-    if (!response.options.inject) {
-      const urls = response.options.urls.split('\n').filter(Boolean).join('|');
-      if (!location.href.match(new RegExp(urls))) return;
-    }
-
-    window.devToolsOptions = response.options;
-    window.__REDUX_DEVTOOLS_EXTENSION__.notifyErrors();
-  }
-);
diff --git a/extension/src/browser/extension/manifest.json b/extension/src/browser/extension/manifest.json
index 36cb428c..b3a9c270 100644
--- a/extension/src/browser/extension/manifest.json
+++ b/extension/src/browser/extension/manifest.json
@@ -52,11 +52,7 @@
     }
   ],
   "devtools_page": "devtools.html",
-  "web_accessible_resources": [
-    "page.bundle.js",
-    "inject.bundle.js",
-    "redux-devtools-extension.bundle.js"
-  ],
+  "web_accessible_resources": ["page.bundle.js"],
   "externally_connectable": {
     "ids": ["*"]
   },
diff --git a/extension/src/browser/firefox/manifest.json b/extension/src/browser/firefox/manifest.json
index 0dfb4e3a..6ab932dd 100644
--- a/extension/src/browser/firefox/manifest.json
+++ b/extension/src/browser/firefox/manifest.json
@@ -49,11 +49,7 @@
     }
   ],
   "devtools_page": "devtools.html",
-  "web_accessible_resources": [
-    "page.bundle.js",
-    "inject.bundle.js",
-    "redux-devtools-extension.bundle.js"
-  ],
+  "web_accessible_resources": ["page.bundle.js"],
   "permissions": [
     "notifications",
     "contextMenus",
diff --git a/extension/webpack/base.config.js b/extension/webpack/base.config.js
index 0fde60d6..12df083c 100644
--- a/extension/webpack/base.config.js
+++ b/extension/webpack/base.config.js
@@ -18,11 +18,6 @@ const baseConfig = (params) => ({
     devtools: [`${extpath}devtools/index`],
     content: [mock, `${extpath}inject/contentScript`],
     pagewrap: [`${extpath}inject/pageScriptWrap`],
-    'redux-devtools-extension': [
-      `${extpath}inject/index`,
-      `${extpath}inject/deprecatedWarn`,
-    ],
-    inject: [`${extpath}inject/index`, `${extpath}inject/deprecatedWarn`],
     ...params.inputExtra,
   },
   output: {