diff --git a/entrypoints/content.ts b/entrypoints/content.ts
index 09975a5..be76ab3 100644
--- a/entrypoints/content.ts
+++ b/entrypoints/content.ts
@@ -204,7 +204,7 @@ export default defineContentScript({
 
     function isExtensionValid(): boolean {
       try {
-        return !!chrome.runtime?.id;
+        return typeof chrome !== 'undefined' && !!chrome.runtime?.id;
       } catch {
         return false;
       }
@@ -223,6 +223,25 @@ export default defineContentScript({
       setTimeout(() => toast.remove(), 4000);
     }
 
+    // ─── Safe chrome.runtime.sendMessage wrapper ──────────────────────────────
+
+    async function safeSendMessage(payload: Record<string, unknown>): Promise<unknown> {
+      if (!isExtensionValid()) {
+        showErrorToast('LexAI was updated — please refresh this page.');
+        return null;
+      }
+      try {
+        return await chrome.runtime.sendMessage(payload);
+      } catch (err) {
+        if (String(err).includes('Extension context invalidated') ||
+            String(err).includes('message channel closed')) {
+          showErrorToast('LexAI was updated — please refresh this page.');
+          hideToolbar();
+        }
+        return null;
+      }
+    }
+
     // ─── LLM call ─────────────────────────────────────────────────────────────
 
     async function runAction(action: string) {
@@ -251,13 +270,15 @@ export default defineContentScript({
       }
 
       try {
-        const response = await chrome.runtime.sendMessage({
+        const response = await safeSendMessage({
           type:    'ANALYZE_TEXT',
           payload: { text: textToProcess, action },
-        });
+        }) as { error?: string; result?: string } | null;
 
         hideToolbar();
 
+        if (response === null) return; // safeSendMessage already handled the error
+
         if (response?.error) {
           showModal(`❌ ${response.error}`, null);
         } else {
@@ -265,8 +286,9 @@ export default defineContentScript({
         }
       } catch (err) {
         hideToolbar();
-        if (String(err).includes('Extension context invalidated')) {
-          showErrorToast('LexAI was updated. Please refresh the page.');
+        if (String(err).includes('Extension context invalidated') ||
+            String(err).includes('message channel closed')) {
+          showErrorToast('LexAI was updated — please refresh this page.');
         } else {
           showModal(`❌ Error: ${String(err)}`, null);
         }
@@ -440,6 +462,25 @@ export default defineContentScript({
       document.body.appendChild(modal);
     }
 
+    // ─── Global extension context error handlers ──────────────────────────────
+
+    window.addEventListener('error', (e) => {
+      if (e.message?.includes('Extension context invalidated')) {
+        e.preventDefault(); // suppress console error
+        hideToolbar();
+        showErrorToast('LexAI was updated — please refresh this page.');
+      }
+    });
+
+    window.addEventListener('unhandledrejection', (e) => {
+      if (String(e.reason)?.includes('Extension context invalidated') ||
+          String(e.reason)?.includes('message channel closed')) {
+        e.preventDefault();
+        hideToolbar();
+        showErrorToast('LexAI was updated — please refresh this page.');
+      }
+    });
+
     // ─── Event listeners ──────────────────────────────────────────────────────
 
     document.addEventListener('mouseup', (e) => {
diff --git a/entrypoints/options/Options.tsx b/entrypoints/options/Options.tsx
index 11ad017..9ff2758 100644
--- a/entrypoints/options/Options.tsx
+++ b/entrypoints/options/Options.tsx
@@ -151,6 +151,30 @@ const styles = {
   } as React.CSSProperties,
 };
 
+// ─── Safe chrome storage wrappers ────────────────────────────────────────────
+
+function safeStorageGet(keys: string[], callback: (result: Record<string, string>) => void) {
+  try {
+    if (typeof chrome === 'undefined' || !chrome.runtime?.id) return;
+    chrome.storage.local.get(keys, callback);
+  } catch (err) {
+    console.warn('LexAI: Extension context invalidated', err);
+  }
+}
+
+function safeStorageSet(data: Record<string, string>, callback?: () => void) {
+  try {
+    if (typeof chrome === 'undefined' || !chrome.runtime?.id) return;
+    if (callback) {
+      chrome.storage.local.set(data, callback);
+    } else {
+      chrome.storage.local.set(data);
+    }
+  } catch (err) {
+    console.warn('LexAI: Extension context invalidated', err);
+  }
+}
+
 // ─── Component ────────────────────────────────────────────────────────────────
 
 function OptionsPage() {
@@ -162,7 +186,7 @@ function OptionsPage() {
   const apiKeyRef = useRef<HTMLInputElement>(null);
 
   useEffect(() => {
-    chrome.storage.local.get(["provider", "apiKey", "model"], (result: Record<string, string>) => {
+    safeStorageGet(["provider", "apiKey", "model"], (result) => {
       if (result.provider) setProvider(result.provider);
       if (result.apiKey) setApiKey(result.apiKey);
       if (result.model) setModel(result.model);
@@ -183,7 +207,7 @@ function OptionsPage() {
       return;
     }
     setSaveStatus('saving');
-    chrome.storage.local.set({ provider, apiKey: apiKey.trim(), model }, () => {
+    safeStorageSet({ provider, apiKey: apiKey.trim(), model }, () => {
       if (chrome.runtime.lastError) {
         setSaveStatus('error');
         setTimeout(() => setSaveStatus('idle'), 3000);
diff --git a/entrypoints/popup/Popup.tsx b/entrypoints/popup/Popup.tsx
index 95b44cb..5432938 100644
--- a/entrypoints/popup/Popup.tsx
+++ b/entrypoints/popup/Popup.tsx
@@ -1,13 +1,24 @@
 import React, { useEffect, useState } from 'react';
 import { createRoot } from 'react-dom/client';
 
+// ─── Safe chrome storage wrapper ─────────────────────────────────────────────
+
+function safeStorageGet(keys: string[], callback: (result: Record<string, string>) => void) {
+  try {
+    if (typeof chrome === 'undefined' || !chrome.runtime?.id) return;
+    chrome.storage.local.get(keys, callback);
+  } catch (err) {
+    console.warn('LexAI: Extension context invalidated', err);
+  }
+}
+
 function Popup() {
   const [configured, setConfigured] = useState(false);
   const [provider, setProvider] = useState('');
   const [model, setModel] = useState('');
 
   useEffect(() => {
-    chrome.storage.local.get(["provider", "apiKey", "model"], (result: Record<string, string>) => {
+    safeStorageGet(["provider", "apiKey", "model"], (result) => {
       if (result.apiKey) {
         setConfigured(true);
         setProvider(result.provider || 'openai');
@@ -16,7 +27,15 @@ function Popup() {
     });
   }, []);
 
-  const openSettings = () => chrome.runtime.openOptionsPage();
+  const openSettings = () => {
+    try {
+      if (typeof chrome !== 'undefined' && chrome.runtime?.id) {
+        chrome.runtime.openOptionsPage();
+      }
+    } catch (err) {
+      console.warn('LexAI: Extension context invalidated', err);
+    }
+  };
 
   return (
     <div style={{ padding: 16, fontFamily: 'system-ui, sans-serif', color: '#1e1e2e' }}>