修改示例

demo/background.html

@@ -18,6 +18,7 @@
 		<h1>这是背景页</h1>
 		<div>
 			<a href="#" id="test_cors">跨域演示</a>
+			<a href="#" id="get_popup_title">获取popup页标题</a>
 		</div>
 	</div>
 	<script type="text/javascript" src="js/jquery-1.8.3.js"></script>

demo/js/background.js

@@ -63,6 +63,15 @@ $('#test_cors').click((e) => {
 	});
 });
 
+$('#get_popup_title').click(e => {
+	var views = chrome.extension.getViews({type:'popup'});
+	if(views.length > 0) {
+		alert(views[0].document.title);
+	} else {
+		alert('popup未打开！');
+	}
+});
+
 // 获取当前选项卡ID
 function getCurrentTabId(callback)
 {