diff --git a/packages/lexical-devtools/README.md b/packages/lexical-devtools/README.md
index 7e1b7b579d8..74d27cb9925 100644
--- a/packages/lexical-devtools/README.md
+++ b/packages/lexical-devtools/README.md
@@ -16,6 +16,7 @@ $ npm run dev
 - Extension activity log: [chrome://extensions/?activity=eddfjidloofnnmloonifcjkpmfmlblab](chrome://extensions/?activity=eddfjidloofnnmloonifcjkpmfmlblab)
 - Status of ServiceWorkers: [chrome://serviceworker-internals/?devtools](chrome://serviceworker-internals/?devtools)
 - WXT Framework debugging: `DEBUG_WXT=1 npm run dev`
+- If you detach the Dev Tools in a separate window, and press `Cmd+Option+I` while Dev Tools window is focused, you will invoke the Dev Tools for the Dev Tools window.
 
 ## Design
 
diff --git a/packages/lexical-devtools/src/components/EditorsRefreshCTA.tsx b/packages/lexical-devtools/src/components/EditorsRefreshCTA.tsx
index 22bb8d1373b..01986bf2b88 100644
--- a/packages/lexical-devtools/src/components/EditorsRefreshCTA.tsx
+++ b/packages/lexical-devtools/src/components/EditorsRefreshCTA.tsx
@@ -30,7 +30,7 @@ function EditorsRefreshCTA({tabID, setErrorMessage}: Props) {
     );
 
     injectedPegasusService
-      .refreshLexicalEditorsForTabID()
+      .refreshLexicalEditors()
       .catch((err) => {
         setErrorMessage(err.message);
         console.error(err);
diff --git a/packages/lexical-devtools/src/entrypoints/background/ActionIconWatchdog.ts b/packages/lexical-devtools/src/entrypoints/background/ActionIconWatchdog.ts
new file mode 100644
index 00000000000..124d67f54b7
--- /dev/null
+++ b/packages/lexical-devtools/src/entrypoints/background/ActionIconWatchdog.ts
@@ -0,0 +1,100 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ */
+import type {Tabs} from 'wxt/browser';
+import type {StoreApi} from 'zustand';
+
+import {IS_FIREFOX} from 'shared/environment';
+
+import {ExtensionState} from '../../store';
+
+export default class ActionIconWatchdog {
+  private constructor(
+    private readonly extensionStore: StoreApi<ExtensionState>,
+  ) {}
+
+  static async start(store: StoreApi<ExtensionState>) {
+    return new ActionIconWatchdog(store).init();
+  }
+
+  async init() {
+    const tabs = await browser.tabs.query({});
+    await Promise.all(
+      tabs.map(this.checkAndHandleRestrictedPageIfSo.bind(this)),
+    );
+
+    browser.tabs.onCreated.addListener((tab) => {
+      this.checkAndHandleRestrictedPageIfSo(tab);
+    });
+
+    // Listen to URL changes on the active tab and update the DevTools icon.
+    browser.tabs.onUpdated.addListener(this.handleTabsUpdatedEvent.bind(this));
+  }
+
+  private async setIcon(
+    lexicalBuildType: 'restricted' | 'enabled',
+    tabId: number,
+  ) {
+    const action = IS_FIREFOX ? browser.browserAction : browser.action;
+
+    await action.setIcon({
+      path: {
+        '128': browser.runtime.getURL(
+          lexicalBuildType === 'enabled'
+            ? '/icon/128.png'
+            : '/icon/128-restricted.png',
+        ),
+        '16': browser.runtime.getURL(
+          lexicalBuildType === 'enabled'
+            ? '/icon/16.png'
+            : '/icon/16-restricted.png',
+        ),
+        '32': browser.runtime.getURL(
+          lexicalBuildType === 'enabled'
+            ? '/icon/32.png'
+            : '/icon/32-restricted.png',
+        ),
+        '48': browser.runtime.getURL(
+          lexicalBuildType === 'enabled'
+            ? '/icon/48.png'
+            : '/icon/48-restricted.png',
+        ),
+      },
+      tabId: tabId,
+    });
+
+    if (lexicalBuildType === 'restricted') {
+      this.extensionStore.getState().markTabAsRestricted(tabId);
+    }
+  }
+
+  private handleTabsUpdatedEvent(
+    tabId: number,
+    _changeInfo: unknown,
+    tab: Tabs.Tab,
+  ): void {
+    this.checkAndHandleRestrictedPageIfSo(tab);
+  }
+
+  private isRestrictedBrowserPage(url: string | undefined) {
+    return (
+      !url || ['chrome:', 'about:', 'file:'].includes(new URL(url).protocol)
+    );
+  }
+
+  private async checkAndHandleRestrictedPageIfSo(tab: Tabs.Tab) {
+    if (tab.id == null) {
+      return;
+    }
+
+    if (tab.id == null || this.isRestrictedBrowserPage(tab.url)) {
+      return this.setIcon('restricted', tab.id);
+    }
+
+    return this.setIcon('enabled', tab.id);
+  }
+}
diff --git a/packages/lexical-devtools/src/entrypoints/background/index.ts b/packages/lexical-devtools/src/entrypoints/background/index.ts
index d0c1de4e14e..4dd130799d4 100644
--- a/packages/lexical-devtools/src/entrypoints/background/index.ts
+++ b/packages/lexical-devtools/src/entrypoints/background/index.ts
@@ -9,7 +9,11 @@
 import {registerRPCService} from '@webext-pegasus/rpc';
 import {initPegasusTransport} from '@webext-pegasus/transport/background';
 
-import {initExtensionStoreBackend} from '../../store.ts';
+import {
+  initExtensionStoreBackend,
+  useExtensionStore as extensionStore,
+} from '../../store.ts';
+import ActionIconWatchdog from './ActionIconWatchdog.ts';
 import {getTabIDService} from './getTabIDService';
 
 export default defineBackground(() => {
@@ -20,4 +24,6 @@ export default defineBackground(() => {
   // Store initialization so other extension surfaces can use it
   // as all changes go through background SW
   initExtensionStoreBackend();
+
+  ActionIconWatchdog.start(extensionStore).catch(console.error);
 });
diff --git a/packages/lexical-devtools/src/entrypoints/devtools-panel/components/EditorInspectorButton.tsx b/packages/lexical-devtools/src/entrypoints/devtools-panel/components/EditorInspectorButton.tsx
index fcbb980ffad..d1019b92303 100644
--- a/packages/lexical-devtools/src/entrypoints/devtools-panel/components/EditorInspectorButton.tsx
+++ b/packages/lexical-devtools/src/entrypoints/devtools-panel/components/EditorInspectorButton.tsx
@@ -24,10 +24,13 @@ export function EditorInspectorButton({tabID, setErrorMessage}: Props) {
       {context: 'window', tabId: tabID},
     );
 
-    injectedPegasusService.toggleEditorPicker().catch((err) => {
-      setErrorMessage(err.message);
-      console.error(err);
-    });
+    injectedPegasusService
+      .refreshLexicalEditors()
+      .then(() => injectedPegasusService.toggleEditorPicker())
+      .catch((err) => {
+        setErrorMessage(err.message);
+        console.error(err);
+      });
   };
 
   return (
diff --git a/packages/lexical-devtools/src/entrypoints/injected/InjectedPegasusService.ts b/packages/lexical-devtools/src/entrypoints/injected/InjectedPegasusService.ts
index 176de0f1598..664006f0fb1 100644
--- a/packages/lexical-devtools/src/entrypoints/injected/InjectedPegasusService.ts
+++ b/packages/lexical-devtools/src/entrypoints/injected/InjectedPegasusService.ts
@@ -40,7 +40,7 @@ export class InjectedPegasusService
     private readonly commandLog: WeakMap<LexicalEditor, LexicalCommandLog>,
   ) {}
 
-  refreshLexicalEditorsForTabID() {
+  refreshLexicalEditors() {
     scanAndListenForEditors(this.tabID, this.extensionStore, this.commandLog);
   }
 
diff --git a/packages/lexical-devtools/src/entrypoints/popup/App.css b/packages/lexical-devtools/src/entrypoints/popup/App.css
index 72a3cbc4bf1..e6bd89156df 100644
--- a/packages/lexical-devtools/src/entrypoints/popup/App.css
+++ b/packages/lexical-devtools/src/entrypoints/popup/App.css
@@ -17,17 +17,3 @@ body {
   margin: 0 auto;
   padding: 1rem;
 }
-
-.logo {
-  height: 2em;
-  /* padding: 1.5em; */
-  will-change: filter;
-  transition: filter 300ms;
-}
-.logo:hover {
-  filter: drop-shadow(0 0 2em #61dafbaa);
-}
-
-.card {
-  padding-top: 2em;
-}
diff --git a/packages/lexical-devtools/src/entrypoints/popup/App.tsx b/packages/lexical-devtools/src/entrypoints/popup/App.tsx
index 2887b4f1f04..05733be0c3d 100644
--- a/packages/lexical-devtools/src/entrypoints/popup/App.tsx
+++ b/packages/lexical-devtools/src/entrypoints/popup/App.tsx
@@ -7,11 +7,10 @@
  */
 import './App.css';
 
+import {Box, Flex} from '@chakra-ui/react';
 import * as React from 'react';
 import {useState} from 'react';
 
-import lexicalLogo from '@/public/lexical.svg';
-
 import EditorsRefreshCTA from '../../components/EditorsRefreshCTA';
 import {useExtensionStore} from '../../store';
 
@@ -27,38 +26,46 @@ function App({tabID}: Props) {
   const lexicalCount = Object.keys(states ?? {}).length;
 
   return (
-    <>
-      <div>
-        <a href="https://lexical.dev" target="_blank">
-          <img src={lexicalLogo} className="logo" alt="Lexical logo" />
-        </a>
-      </div>
+    <Flex direction="column">
       {errorMessage !== '' ? (
-        <div className="card error">{errorMessage}</div>
+        <Box className="error" mb={2} color="red">
+          {errorMessage}
+        </Box>
       ) : null}
-      <div className="card">
-        {states === undefined ? (
-          <span>Loading...</span>
-        ) : (
+      <Box>
+        {states === null ? (
           <span>
-            Found <b>{lexicalCount}</b> editor{lexicalCount > 1 ? 's' : ''} on
-            the page
-            {lexicalCount > 0 ? (
-              <>
-                {' '}
-                &#x2705;
-                <br />
-                Open the developer tools, and "Lexical" tab will appear to the
-                right.
-              </>
-            ) : null}
+            This is a restricted browser page. Lexical DevTools cannot access
+            this page.
           </span>
+        ) : states === undefined ? (
+          <span>Loading...</span>
+        ) : (
+          <>
+            <Box>
+              Found <b>{lexicalCount}</b> editor
+              {lexicalCount > 1 || lexicalCount === 0 ? 's' : ''} on the page
+              {lexicalCount > 0 ? (
+                <>
+                  {' '}
+                  &#x2705;
+                  <br />
+                  Open the developer tools, and "Lexical" tab will appear to the
+                  right.
+                </>
+              ) : null}
+            </Box>
+
+            <Box mt={1}>
+              <EditorsRefreshCTA
+                tabID={tabID}
+                setErrorMessage={setErrorMessage}
+              />
+            </Box>
+          </>
         )}
-        <p>
-          <EditorsRefreshCTA tabID={tabID} setErrorMessage={setErrorMessage} />
-        </p>
-      </div>
-    </>
+      </Box>
+    </Flex>
   );
 }
 
diff --git a/packages/lexical-devtools/src/lexicalForExtension.ts b/packages/lexical-devtools/src/lexicalForExtension.ts
index bdd537f3d1e..3b45ed74f52 100644
--- a/packages/lexical-devtools/src/lexicalForExtension.ts
+++ b/packages/lexical-devtools/src/lexicalForExtension.ts
@@ -59,17 +59,25 @@ export function $getSelection(): null | lexical.BaseSelection {
 export function $isElementNode(
   node: lexical.LexicalNode | null | undefined,
 ): node is lexical.ElementNode {
+  if (node == null) {
+    return false;
+  }
+
   const editor = getActiveEditor();
-  const ElementNode = Object.getPrototypeOf(
-    editor._nodes.get('paragraph')!.klass,
-  );
+  const ParagraphNode = editor._nodes.get('paragraph')!.klass;
+  const ElementNode = Object.getPrototypeOf(ParagraphNode.prototype);
 
-  return node instanceof ElementNode;
+  // eslint-disable-next-line no-prototype-builtins
+  return ElementNode.isPrototypeOf(node);
 }
 
 export function $isTextNode(
   node: lexical.LexicalNode | null | undefined,
 ): node is lexical.TextNode {
+  if (node == null) {
+    return false;
+  }
+
   const editor = getActiveEditor();
   const TextNode = editor._nodes.get('text')!.klass;
 
diff --git a/packages/lexical-devtools/src/public/icon/128-restricted.png b/packages/lexical-devtools/src/public/icon/128-restricted.png
new file mode 100644
index 00000000000..781567d2fbe
Binary files /dev/null and b/packages/lexical-devtools/src/public/icon/128-restricted.png differ
diff --git a/packages/lexical-devtools/src/public/icon/16-restricted.png b/packages/lexical-devtools/src/public/icon/16-restricted.png
new file mode 100644
index 00000000000..c97f6ffce25
Binary files /dev/null and b/packages/lexical-devtools/src/public/icon/16-restricted.png differ
diff --git a/packages/lexical-devtools/src/public/icon/32-restricted.png b/packages/lexical-devtools/src/public/icon/32-restricted.png
new file mode 100644
index 00000000000..26d39aa852f
Binary files /dev/null and b/packages/lexical-devtools/src/public/icon/32-restricted.png differ
diff --git a/packages/lexical-devtools/src/public/icon/48-restricted.png b/packages/lexical-devtools/src/public/icon/48-restricted.png
new file mode 100644
index 00000000000..dcde663ad7f
Binary files /dev/null and b/packages/lexical-devtools/src/public/icon/48-restricted.png differ
diff --git a/packages/lexical-devtools/src/store.ts b/packages/lexical-devtools/src/store.ts
index 8b38b0a475b..3926e9830a6 100644
--- a/packages/lexical-devtools/src/store.ts
+++ b/packages/lexical-devtools/src/store.ts
@@ -17,11 +17,12 @@ import {SerializedRawEditorState} from './types';
 
 export interface ExtensionState {
   lexicalState: {
-    [tabID: number]: {[editorKey: string]: SerializedRawEditorState};
+    [tabID: number]: {[editorKey: string]: SerializedRawEditorState} | null;
   };
   selectedEditorKey: {
     [tabID: number]: string | null;
   };
+  markTabAsRestricted: (tabID: number) => void;
   setStatesForTab: (
     id: number,
     states: {[editorKey: string]: SerializedRawEditorState},
@@ -32,6 +33,13 @@ export interface ExtensionState {
 export const useExtensionStore = create<ExtensionState>()(
   subscribeWithSelector((set) => ({
     lexicalState: {},
+    markTabAsRestricted: (tabID: number) =>
+      set((state) => ({
+        lexicalState: {
+          ...state.lexicalState,
+          [tabID]: null,
+        },
+      })),
     selectedEditorKey: {},
     setSelectedEditorKey: (tabID: number, editorKey: string | null) =>
       set((state) => ({