remove default replacing for new tab and make it optional.

src/eventPage.js

@@ -0,0 +1,22 @@
+chrome.tabs.onCreated.addListener(function (tab) {
+
+	console.log('created', arguments)
+	if (tab.url === 'chrome://newtab/') {
+		chrome.tabs.update(tab.id, {
+			url: chrome.extension.getURL('index.html')
+		}, function callback() {
+			console.log('ho gaya');
+		});
+	}
+
+});
+
+chrome.tabs.onUpdated.addListener(function () {
+
+	console.log('updated', arguments)
+
+});
+
+chrome.browserAction.onClicked.addListener(function(activeTab) {
+    chrome.tabs.create({ url: chrome.extension.getURL('index.html'), selected: true });
+});

src/manifest.json

@@ -3,13 +3,19 @@
 	"version": "1.3",
 	"manifest_version": 2,
 	"description": "Convert new tabs into an offline playground for your web experiments",
-	"chrome_url_overrides" : {
-		"newtab": "index.html"
-	},
 	"homepage_url": "https://kushagragour.in/lab/web-maker",
 	"permissions": [
-		"storage"
+		"storage",
+		"tabs"
 	],
+	"browser_action": {
+		"default_title": "Start Web Maker",
+		"default_icon": "icon-16.png"
+	},
+	"background": {
+		"scripts": [ "eventPage.js" ],
+		"persistent": false
+	},
 	"content_security_policy": "script-src 'self' 'unsafe-eval'; object-src 'self'",
 	"icons": {
 		"16": "icon-16.png",