diff --git a/core/browser.py b/core/browser.py
index 9c098d6..134d8a7 100644
--- a/core/browser.py
+++ b/core/browser.py
@@ -38,14 +38,11 @@ class BrowserView(QtWebEngineWidgets.QWebEngineView):
         self.web_page = BrowserPage()
         self.setPage(self.web_page)
 
-        self.event_widgets = []
-
     def event(self, event):
         if event.type() == QEvent.ChildAdded:
             obj = event.child()
             if isinstance(obj, QWidget):
                 obj.installEventFilter(self)
-                self.event_widgets.append(obj)
 
         return QtWebEngineWidgets.QWebEngineView.event(self, event)
 
diff --git a/core/browser_buffer.py b/core/browser_buffer.py
index d8ba252..59da8af 100644
--- a/core/browser_buffer.py
+++ b/core/browser_buffer.py
@@ -19,6 +19,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+from PyQt5 import QtCore
 from core.browser import BrowserView, webview_scroll
 from core.buffer import Buffer
 
@@ -29,6 +30,10 @@ class BrowserBuffer(Buffer):
 
         self.add_widget(BrowserView())
 
+        self.buffer_widget.loadStarted.connect(self.start_progress)
+        self.buffer_widget.loadProgress.connect(self.update_progress)
+        self.buffer_widget.loadFinished.connect(self.stop_progress)
+
     def get_key_event_widgets(self):
         # We need send key event to QWebEngineView's focusProxy widget, not QWebEngineView.
         return [self.buffer_widget.focusProxy()]
diff --git a/core/buffer.py b/core/buffer.py
index 00d7788..2e99645 100644
--- a/core/buffer.py
+++ b/core/buffer.py
@@ -20,7 +20,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from PyQt5 import QtCore
-from PyQt5.QtGui import QBrush
+from PyQt5.QtGui import QBrush, QColor
 from PyQt5.QtWidgets import QGraphicsScene, QApplication
 import abc
 from core.utils import PostGui
@@ -44,17 +44,43 @@ class Buffer(QGraphicsScene):
 
         self.buffer_widget = None
 
+        self.draw_progressbar = False
+        self.progressbar_progress = 0
+        self.progressbar_color = QColor(233, 129, 35, 255)
+        self.progressbar_height = 2
+
+    def drawForeground(self, painter, rect):
+        if self.draw_progressbar:
+            painter.setBrush(self.progressbar_color)
+            painter.setPen(self.progressbar_color)
+            painter.drawRect(0, 0, rect.width() * self.progressbar_progress * 1.0 / 100, self.progressbar_height)
+
+    @QtCore.pyqtSlot()
+    def start_progress(self):
+        self.progressbar_progress = 0
+        self.draw_progressbar = True
+        self.update()
+
+    @QtCore.pyqtSlot()
+    def stop_progress(self):
+        self.draw_progressbar = False
+        self.update()
+
+    @QtCore.pyqtSlot(int)
+    def update_progress(self, progress):
+        self.progressbar_progress = progress
+        self.draw_progressbar = True
+        self.update()
+
+        if progress == 100:
+            QtCore.QTimer.singleShot(500, self.stop_progress)
+
     def add_widget(self, widget):
         self.buffer_widget = widget
         self.addWidget(self.buffer_widget)
 
         self.buffer_widget.installEventFilter(self)
 
-    def eventFitler(self, event):
-        print("8u3947923473924732 ", event.type())
-
-        return False
-
     def handle_destroy(self):
         self.before_destroy_hook.emit()
 
diff --git a/docs/HACKING.md b/docs/HACKING.md
index 381e58d..74e6476 100644
--- a/docs/HACKING.md
+++ b/docs/HACKING.md
@@ -201,5 +201,16 @@ If you want handle keystroke send from Emacs, you just need implement interface
 
 Argument "keystroke" is emacs key string.
 
+### Update progress.
+
+If your application will do some long-time operation, you can use below use below interfaces of buffer:
+
+```Python
+    def start_progress(self):
+    def stop_progress(self):
+    def update_progress(self, progress):
+```	
+
+
 ## Todolist
 [Some works you can hacking ;)](TODOLIST.md)
diff --git a/docs/TODOLIST.md b/docs/TODOLIST.md
index af82870..66dfc26 100644
--- a/docs/TODOLIST.md
+++ b/docs/TODOLIST.md
@@ -2,7 +2,6 @@
 * Core: Remove border of QGraphicsView.
 * Browser: add cookie support
 * Browser: support pop window, such as emacs-china.org
-* Browser: add progressbar
 * Browser: add proxy support
 * Browser: implement js plugin like vimium
 * Browser: study more code from https://github.com/LavaPower/Browthon-Old/blob/c25d5721b40e95131a3c521566a18467f13ecbf0/files/Browthon_elements.py