diff --git a/src/background/main.js b/src/background/main.js
index 3fecec5..f7c1e34 100644
--- a/src/background/main.js
+++ b/src/background/main.js
@@ -132,21 +132,21 @@ async function removeMenuItem(menuItemId, {throwError = false} = {}) {
 }
 
 async function createMenu() {
-  const menuKey = browser.extension.inIncognitoContext
-    ? 'privateMenuItems'
-    : 'menuItems';
+  const context = {
+    name: 'private',
+    active: browser.extension.inIncognitoContext
+  };
 
-  const {showInContextMenu, [menuKey]: currentItems} = await storage.get([
-    'showInContextMenu',
-    menuKey
-  ]);
+  const {menuItems: currentItems} = await storage.get('menuItems', {context});
 
   for (const itemId of currentItems) {
     await removeMenuItem(itemId);
   }
 
+  const {showInContextMenu} = await storage.get('showInContextMenu');
   const newItems = showInContextMenu ? await getMenuItems() : [];
-  await storage.set({[menuKey]: newItems.map(item => item.id)});
+
+  await storage.set({menuItems: newItems.map(item => item.id)}, {context});
 
   try {
     for (const item of newItems) {
@@ -599,7 +599,7 @@ async function execEngine(tabId, engine, taskId) {
   await executeScript({
     func: taskId => (self.taskId = taskId),
     args: [taskId],
-    code: `var taskId = '${taskId}';`,
+    code: `self.taskId = '${taskId}'`,
     tabId
   });
   await executeScript({files: ['/src/commons-engine/script.js'], tabId});
@@ -637,7 +637,7 @@ async function openCurrentDoc({linkUrl} = {}) {
     if (await hasModule({tabId: activeTab.id, module: 'tools', insert: true})) {
       await executeScript({
         func: () => self.openCurrentDoc(),
-        code: `openCurrentDoc()`,
+        code: `self.openCurrentDoc()`,
         tabId: activeTab.id
       });
     } else {
diff --git a/src/storage/storage.js b/src/storage/storage.js
index 2e86a4b..b218be6 100755
--- a/src/storage/storage.js
+++ b/src/storage/storage.js
@@ -1,3 +1,4 @@
+import {capitalizeFirstLetter, lowercaseFirstLetter} from 'utils/common';
 import {storageRevisions} from 'utils/config';
 
 async function isStorageArea({area = 'local'} = {}) {
@@ -49,19 +50,67 @@ async function ensureStorageReady({area = 'local'} = {}) {
   }
 }
 
-async function get(keys = null, {area = 'local'} = {}) {
+function encodeStorageData(data, context) {
+  if (context?.active) {
+    if (typeof data === 'string') {
+      return `${context.name}${capitalizeFirstLetter(data)}`;
+    } else if (Array.isArray(data)) {
+      const items = [];
+
+      for (const item of data) {
+        items.push(`${context.name}${capitalizeFirstLetter(item)}`);
+      }
+
+      return items;
+    } else {
+      const items = {};
+
+      for (const [key, value] of Object.entries(data)) {
+        items[`${context.name}${capitalizeFirstLetter(key)}`] = value;
+      }
+
+      return items;
+    }
+  }
+
+  return data;
+}
+
+function decodeStorageData(data, context) {
+  if (context?.active) {
+    const items = {};
+
+    for (const [key, value] of Object.entries(data)) {
+      items[
+        lowercaseFirstLetter(key.replace(new RegExp(`^${context.name}`), ''))
+      ] = value;
+    }
+
+    return items;
+  }
+
+  return data;
+}
+
+async function get(keys = null, {area = 'local', context = null} = {}) {
   await ensureStorageReady({area});
-  return browser.storage[area].get(keys);
+
+  return decodeStorageData(
+    await browser.storage[area].get(encodeStorageData(keys, context)),
+    context
+  );
 }
 
-async function set(obj, {area = 'local'} = {}) {
+async function set(obj, {area = 'local', context = null} = {}) {
   await ensureStorageReady({area});
-  return browser.storage[area].set(obj);
+
+  return browser.storage[area].set(encodeStorageData(obj, context));
 }
 
-async function remove(keys, {area = 'local'} = {}) {
+async function remove(keys, {area = 'local', context = null} = {}) {
   await ensureStorageReady({area});
-  return browser.storage[area].remove(keys);
+
+  return browser.storage[area].remove(encodeStorageData(keys, context));
 }
 
 async function clear({area = 'local'} = {}) {
@@ -70,4 +119,4 @@ async function clear({area = 'local'} = {}) {
 }
 
 export default {get, set, remove, clear};
-export {isStorageArea, isStorageReady, ensureStorageReady};
+export {isStorageArea, isStorageReady};
diff --git a/src/utils/common.js b/src/utils/common.js
index 440a2fe..1e79fdd 100644
--- a/src/utils/common.js
+++ b/src/utils/common.js
@@ -346,6 +346,14 @@ function getRandomInt(min, max) {
   return Math.floor(Math.random() * (max - min + 1)) + min;
 }
 
+function capitalizeFirstLetter(string, {locale = 'en-US'} = {}) {
+  return string.replace(/^\p{CWU}/u, char => char.toLocaleUpperCase(locale));
+}
+
+function lowercaseFirstLetter(string, {locale = 'en-US'} = {}) {
+  return string.replace(/^\p{CWL}/u, char => char.toLocaleLowerCase(locale));
+}
+
 function getCharCount(string) {
   return [...string].length;
 }
@@ -547,6 +555,8 @@ export {
   isBackgroundPageContext,
   getExtensionDomain,
   getRandomInt,
+  capitalizeFirstLetter,
+  lowercaseFirstLetter,
   getCharCount,
   querySelectorXpath,
   nodeQuerySelector,