diff --git a/README.md b/README.md
index 42e21ca..114fa33 100644
--- a/README.md
+++ b/README.md
@@ -1,18 +1,17 @@
 # auto skip ads
 youtube広告を自動でスキップします．  
-機能は以上です．
 - 15-30程度の広告のスキップボタンを自動で押します．
-- スキップ不能の広告を16倍で再生します．
+- スキップ不能の広告をスキップします．
 
 **広告自体のブロックはしません**
 
 ## install
 
-### store (推奨)
-[chromewebstoreからinstall](https://chromewebstore.google.com/detail/auto-skip-ads/bladpfbfkeddfhdojdjcopkejlmgapla)からインストール．
+### Store (推奨)
+[Chrome Webstore](https://chromewebstore.google.com/detail/auto-skip-ads/bladpfbfkeddfhdojdjcopkejlmgapla)からインストール．
 
 ### self
-1. cloneかzipをダウンロードする
+1. [最新版のzip](https://github.com/pantyetta/autoskip-ads/releases)をダウンロードする
 2. [拡張機能ページにアクセスする](chrome://extensions/)
 3. 右上ののdeveloper modeを有効にする
 4. パッケージ化されていない拡張機能を読み込む を利用する
diff --git a/background.js b/background.js
index a351528..e4793f4 100644
--- a/background.js
+++ b/background.js
@@ -10,15 +10,11 @@ const skipAds = (tabId) => {
             };
 
             const $player = document.getElementById('movie_player');
-            const video = document.querySelector('video');
 
             const playerObserver = new MutationObserver(() => {
                 const $skip_container =  document.getElementsByClassName("video-ads ytp-ad-module")[0] || null;
-                if(!$skip_container.children.length)    return;
-
-                if(video.currentTime == video.duration)    return;
-
-                video.currentTime = video.duration;
+                console.log("skip container");
+                if($skip_container == null || !$skip_container.children.length)    return;
 
                 const observer = new MutationObserver(() => {
                     const $skip_button = document.getElementsByClassName('ytp-ad-skip-button-modern ytp-button')[0] || null;
@@ -28,8 +24,14 @@ const skipAds = (tabId) => {
 
                     observer.disconnect();
                 });
-                
                 observer.observe($skip_container, config);
+                
+                const video = document.querySelector('video');
+                try {
+                    video.currentTime = video.duration;
+                    console.log('skip ads');
+                } catch (error) {}
+                
             });
             playerObserver.observe($player, config);
         },
@@ -39,17 +41,26 @@ const skipAds = (tabId) => {
 
 const isEmpty = (obj) => {
     return !Object.keys(obj).length;
-  }
+}
+
+chrome.webNavigation.onCommitted.addListener((details) => {
+    if (details.transitionType === 'reload') {
+        chrome.storage.session.remove([details.tabId.toString()]);
+        console.log("remove script");
+    }
+}, {url: [{urlMatches : 'https://www.youtube.com/*'}]});
 
 chrome.tabs.onUpdated.addListener((tabId, changeInfo, tab) => {
     const pattern = /^https:\/\/(www\.)?youtube\.com\/.+/
     if(tab.url.match(pattern) && changeInfo.status === 'complete'){
+
         chrome.storage.session.get([tabId.toString()]).then((result) => {
             if(isEmpty(result)){
+                console.log("insert script");
                 skipAds(tabId);
             }
         });
 
         chrome.storage.session.set({ [tabId]: true });
     }
-})
\ No newline at end of file
+});
\ No newline at end of file
diff --git a/manifest.json b/manifest.json
index 14f9fa9..22ea514 100644
--- a/manifest.json
+++ b/manifest.json
@@ -1,6 +1,6 @@
 {
     "name": "auto skip ads",
-    "version": "1.0.4",
+    "version": "1.0.5",
     "description": "youtube広告をブロックせずにスキップします",
     "manifest_version": 3,
     "background": {
@@ -15,7 +15,8 @@
         "activeTab",
         "tabs",
         "scripting",
-        "storage"
+        "storage",
+        "webNavigation"
     ],
     "host_permissions": [
         "https://www.youtube.com/*",