diff --git a/package.json b/package.json
index dd4608e818153b0aede78315084ee6cd21104367..f7e656a3bed742b1f92243f4e9b2fab32544f11c 100644
--- a/package.json
+++ b/package.json
@@ -7,7 +7,7 @@
   "wechaty": {
     "DEFAULT_HEAD": "chrome",
     "DEFAULT_PUPPET": "web",
-    "DEFAULT_PROFILE": "profile",
+    "DEFAULT_PROFILE": "demo",
     "DEFAULT_PORT": 8788,
     "DEFAULT_PROTOCOL": "io|0.0.1",
     "DEFAULT_TOKEN": "WECHATY_IO_TOKEN",
diff --git a/src/config.ts b/src/config.ts
index 6115bb69f461695647c9719eae2a9115e27d9b6b..d5cc32e07c0b75ee8ce251959319d740749b87aa 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -135,12 +135,14 @@ Object.assign(Config, {
   puppetInstance
 })
 
+export type WatchdogFoodName = 'HEARTBEAT'
+                              | 'POISON'
+                              | 'SCAN'
+
 export type WatchdogFood = {
     data: any
   , timeout?: number  // millisecond
-  , type?:  'HEARTBEAT'
-          | 'POISON'
-          | 'SCAN'
+  , type?: WatchdogFoodName
 }
 
 export type ScanInfo = {
diff --git a/src/puppet-web/browser.ts b/src/puppet-web/browser.ts
index 4105f9c8c1af1b740aa6edf903606e5138642ad0..a68f14b1be1f2e56467b416496d136c6f8aaa860 100644
--- a/src/puppet-web/browser.ts
+++ b/src/puppet-web/browser.ts
@@ -534,7 +534,11 @@ class Browser extends EventEmitter {
   }
 
   public dead(forceReason?: string): boolean {
-    log.verbose('PuppetWebBrowser', 'dead(%s)', forceReason ? forceReason : '')
+    if (forceReason) {
+      log.verbose('PuppetWebBrowser', 'dead(%s)', forceReason)
+    } else {
+      log.silly('PuppetWebBrowser', 'dead()')
+    }
 
     let msg
     let dead = false
diff --git a/src/puppet-web/puppet-web.ts b/src/puppet-web/puppet-web.ts
index e6a3ee34f00aa79c122022b5d8486db72b1e08c1..9093857590eb73e7c77897fb533b360f72e1eee0 100644
--- a/src/puppet-web/puppet-web.ts
+++ b/src/puppet-web/puppet-web.ts
@@ -49,7 +49,10 @@ export class PuppetWeb extends Puppet {
 
   private port: number
 
-  constructor(private setting: PuppetWebSetting = {}) {
+  public lastScanEventTime: number
+  public watchDogLastSaveSession: number
+
+  constructor(public setting: PuppetWebSetting = {}) {
     super()
 
     this.on('watchdog', Watchdog.onFeed.bind(this))
diff --git a/src/puppet-web/watchdog.ts b/src/puppet-web/watchdog.ts
index 922d8cce61f83094ececf22543145130ed5bb0d4..c8f8434b365d2175baf4b6b0b3b01df9834cc2f2 100644
--- a/src/puppet-web/watchdog.ts
+++ b/src/puppet-web/watchdog.ts
@@ -15,12 +15,13 @@
  */
 // const co    = require('co')
 
-import log   from '../brolog-env'
 import {
-  WatchdogFood
-} from '../config'
-
-import Event from './event'
+    WatchdogFood
+  , WatchdogFoodName
+  , log
+}                 from '../config'
+import PuppetWeb  from './puppet-web'
+import Event      from './event'
 
 /* tslint:disable:variable-name */
 const Watchdog = {
@@ -122,11 +123,16 @@ function watchDogReset(timeout, lastFeed) {
  * save every 5 mins
  *
  */
-function autoSaveSession() {
+function autoSaveSession(this: PuppetWeb, force = false) {
+  log.silly('PuppetWebWatchdog', 'autoSaveSession()')
+
+  if (force) {
+    this.watchDogLastSaveSession = 0 // 0 will cause save session right now
+  }
   const SAVE_SESSION_INTERVAL = 5 * 60 * 1000 // 5 mins
   if (Date.now() - this.watchDogLastSaveSession > SAVE_SESSION_INTERVAL) {
-    log.verbose('PuppetWebWatchdog', 'watchDog() saveSession(%s) after %d minutes'
-                                    , this.profile
+    log.verbose('PuppetWebWatchdog', 'autoSaveSession() profile(%s) after %d minutes'
+                                    , this.setting.profile
                                     , Math.floor(SAVE_SESSION_INTERVAL / 1000 / 60)
               )
     this.browser.saveSession()
@@ -143,16 +149,17 @@ function autoSaveSession() {
  * so we need to refresh the page after a while
  *
  */
-function monitorScan(type) {
+function monitorScan(this: PuppetWeb, type: WatchdogFoodName) {
   log.silly('PuppetWebWatchdog', 'monitorScan(%s)', type)
 
   const scanTimeout = 10 * 60 * 1000 // 10 mins
 
   if (type === 'SCAN') { // watchDog was feed a 'scan' data
     this.lastScanEventTime = Date.now()
+    // autoSaveSession.call(this, true)
   }
   if (this.logined()) { // XXX: login status right?
-    this.lastScanEventTime = null
+    this.lastScanEventTime = 0
   } else if (this.lastScanEventTime
               && Date.now() - this.lastScanEventTime > scanTimeout) {
     log.warn('PuppetWebWatchdog', 'monirotScan() refresh browser for no food of type scan after %s mins'
diff --git a/src/room.ts b/src/room.ts
index d523a35c134e046e69e874284b440c54cbca8ac7..58211b1d037f0d015e31a6ab9799278a93b3f139 100644
--- a/src/room.ts
+++ b/src/room.ts
@@ -353,7 +353,7 @@ export class Room extends EventEmitter implements Sayable {
   public static create(contactList: Contact[], topic?: string): Promise<Room> {
     log.verbose('Room', 'create(%s, %s)', contactList.join(','), topic)
 
-    if (!contactList || !(typeof contactList === 'array')) {
+    if (!contactList || !Array.isArray(contactList)) {
       throw new Error('contactList not found')
     }