Added ability to turn extension on and off, added counter badge

Author: Litee

.editorconfig

@@ -0,0 +1,11 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+
+[*.json]
+indent_size = 2
+
+[*.md]
+trim_trailing_whitespace = false

README.md

@@ -1,13 +1,11 @@
 # "Prevent Duplicate Tabs" Chrome extension
 
-Chrome extension that detects when a duplicate tab is opened and activates already existing tab.
+Chrome extension that detects when a duplicate tab is opened and activates already existing tab. You can temporary turn it off by clicking extension's icon. Icon badge is showing the number of prevented duplicates.
 
 ## How to install
 
-I have not published this extension into Chrome Web Store, so your will need to install extension locally:
-
 1. Clone extension to your machine - e.g. `git clone https://github.com/Litee/prevent-duplicate-tabs-chrome-extension.git`
-1. Look at `background.js` and into `manifest.json`. It is always a good idea to check that code does not do anything suspicious and does not have too many permissions ;)
+1. Look into `background.js` and `manifest.json`. It is always a good idea to check that code does not do anything suspicious and does not have too many permissions ;)
 1. Open chrome://extensions tab in your Chrome browser
 1. Activate developer mode (required for next step)
 1. Install extension as unpacked

background.js

@@ -1,11 +1,23 @@
+let preventedDuplicatesCount = 0;
+let active = true;
+
+chrome.browserAction.setBadgeBackgroundColor({
+    color: '#933EC5'
+});
+
+chrome.browserAction.onClicked.addListener(tab => {
+    active = !active;
+    updateBadge();
+});
+
 chrome.tabs.onCreated.addListener(newTab => {
-    if (newTab.url) {
+    if (active && newTab.url) {
         verifyAndDeduplicate(newTab.id, newTab.url);
     }
 });
 
 chrome.tabs.onUpdated.addListener((updatedTabId, updateInfo, updatedTab) => {
-    if (updateInfo.url) {
+    if (active && updateInfo.url) {
         verifyAndDeduplicate(updatedTabId, updateInfo.url);
     }
 });
@@ -26,6 +38,14 @@ function verifyAndDeduplicate(currentTabId, currentTabUrl) {
                 focused: true
             })
             chrome.tabs.remove(currentTabId);
+            preventedDuplicatesCount++;
+            updateBadge();
         }
     });
+}
+
+function updateBadge() {
+    chrome.browserAction.setBadgeText({
+        text: active ? (preventedDuplicatesCount > 0 ? `${preventedDuplicatesCount}` : '') : 'OFF'
+    });
 }

manifest.json

@@ -1,6 +1,6 @@
 {
     "name": "Prevent Duplicate Tabs",
-    "version": "0.0.1",
+    "version": "0.0.2",
     "manifest_version": 2,
     "description": "Chrome extension that detects when a duplicate tab is opened and activates already existing tab",
     "icons": {