diff --git a/src/XExtensionHelper.ts b/src/XExtensionHelper.ts
index 96f320d..bc54aa5 100644
--- a/src/XExtensionHelper.ts
+++ b/src/XExtensionHelper.ts
@@ -8,7 +8,7 @@ class XExtensionHelper {
     // check
     const config = vscode.workspace.getConfiguration(acts.appcfgkey + "." + lang);
     const cmd = config.checker || "";
-    acts.channel.appendLine(`[${acts.timestamp()}] checker: ${cmd}`);
+    acts.channel.appendLine(`checker: ${cmd}`);
     if (!cmd) {
       throw "ERROR: no checker";
     }
@@ -23,7 +23,7 @@ class XExtensionHelper {
     }
     const out = fs.readFileSync(acts.tmpstdoutfile).toString().trim().replace(/\r\n/g, "\n").replace(/\n/g, "\r\n");
     fs.unlinkSync(acts.tmpstdoutfile);
-    acts.channel.appendLine(`[${acts.timestamp()}] - stdout="${out}"`);
+    acts.channel.appendLine(`- stdout="${out}"`);
   }
 
   compileTask(lang: string, opt: object = {}): void {
@@ -31,15 +31,15 @@ class XExtensionHelper {
     const config = vscode.workspace.getConfiguration(acts.appcfgkey + "." + lang);
     const cmd = config.compiler || "";
     if (!cmd) {
-      acts.channel.appendLine(`[${acts.timestamp()}] compiler: ${cmd}`);
+      acts.channel.appendLine(`compiler: ${cmd}`);
     } else {
       let deleted = false;
       if (fs.existsSync(acts.execfile)) {
         fs.unlinkSync(acts.execfile);
         deleted = true;
       }
-      acts.channel.appendLine(`[${acts.timestamp()}] execfile: ${acts.execfile}${deleted ? " deleted" : ""}`);
-      acts.channel.appendLine(`[${acts.timestamp()}] compiler: ${cmd}`);
+      acts.channel.appendLine(`execfile: ${acts.execfile}${deleted ? " deleted" : ""}`);
+      acts.channel.appendLine(`compiler: ${cmd}`);
       const cmdexp = acts.expandString(cmd);
       // 標準エラー出力のリダイレクトをwindowsとwsl2で同じように扱えないため標準出力のみを扱う
       const command = `(${cmdexp}) > ${acts.tmpstdoutfile}`;
@@ -52,13 +52,13 @@ class XExtensionHelper {
       } finally {
         const out = fs.readFileSync(acts.tmpstdoutfile).toString().trim().replace(/\r\n/g, "\n").replace(/\n/g, "\r\n");
         fs.unlinkSync(acts.tmpstdoutfile);
-        acts.channel.appendLine(`[${acts.timestamp()}] - stdout="${out}"`);
+        acts.channel.appendLine(`- stdout="${out}"`);
       }
     }
 
     // show executor
     const cmdexe = config.executor || "";
-    acts.channel.appendLine(`[${acts.timestamp()}] executor: ${cmdexe}`);
+    acts.channel.appendLine(`executor: ${cmdexe}`);
     if (!cmdexe) {
       throw "ERROR: no executor";
     }
diff --git a/src/xsite/AtCoder.ts b/src/xsite/AtCoder.ts
index d7224b5..25496ec 100644
--- a/src/xsite/AtCoder.ts
+++ b/src/xsite/AtCoder.ts
@@ -226,7 +226,7 @@ class AtCoder implements XSite {
     }
     // atcoderでc/c++の場合
     if (this.extension === cpp.extension) {
-      acts.channel.appendLine(`[${acts.timestamp()}] aclibpath: ${this.aclibpath}`);
+      acts.channel.appendLine(`aclibpath: ${this.aclibpath}`);
       // .aclibpathがない場合
       if (!fs.existsSync(this.aclibpath)) {
         // ダウンロード済atcoder libraryがあれば削除
@@ -237,7 +237,7 @@ class AtCoder implements XSite {
           fs.rmSync(this.aclibzip_extractpath, { recursive: true, force: true });
         }
         // atcoder libraryをダウンロード
-        acts.channel.appendLine(`[${acts.timestamp()}] get_aclib: ${this.acliburl}`);
+        acts.channel.appendLine(`get_aclib: ${this.acliburl}`);
         const agent = superagent.agent();
         let response;
         try {
@@ -248,9 +248,9 @@ class AtCoder implements XSite {
             .catch(res => {
               throw acts.responseToMessage(res);
             });
-          acts.channel.appendLine(`[${acts.timestamp()}] -> ${response.status}`);
+          acts.channel.appendLine(`-> ${response.status}`);
         } catch (ex) {
-          acts.channel.appendLine(`[${acts.timestamp()}] -> ${ex}`);
+          acts.channel.appendLine(`-> ${ex}`);
         }
         // ダウンロードできた場合だけファイルに保存して展開
         if (response.status === 200) {
@@ -259,7 +259,7 @@ class AtCoder implements XSite {
           // atcoderフォルダだけプロジェクトフォルダにコピー
           fs.mkdirSync(this.aclibpath, { recursive: true });
           fs.readdirSync(this.aclibzip_aclibpath).forEach(filename => {
-            acts.channel.appendLine(`[${acts.timestamp()}] aclib: ${filename}`);
+            acts.channel.appendLine(`aclib: ${filename}`);
             const src = path.normalize(`${this.aclibzip_aclibpath}/${filename}`);
             const dst = path.normalize(`${this.aclibpath}/${filename}`);
             fs.copyFileSync(src, dst);
@@ -277,25 +277,25 @@ class AtCoder implements XSite {
 
   public async loginSiteAsync() {
     // show channel
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.loginurl: ${this.loginurl}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.username: ${this.username}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.password: ********`);
+    acts.channel.appendLine(`atcoder.loginurl: ${this.loginurl}`);
+    acts.channel.appendLine(`atcoder.username: ${this.username}`);
+    acts.channel.appendLine(`atcoder.password: ********`);
 
     // get agent
     const agent = superagent.agent();
 
     // login get
-    acts.channel.appendLine(`[${acts.timestamp()}] login_get:`);
+    acts.channel.appendLine(`login_get:`);
     const res1 = await agent
       .get(this.loginurl)
       .proxy(acts.proxy)
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res1.status}`);
+    acts.channel.appendLine(`-> ${res1.status}`);
 
     // login post
-    acts.channel.appendLine(`[${acts.timestamp()}] login_post:`);
+    acts.channel.appendLine(`login_post:`);
     const $ = cheerio.load(res1.text);
     const csrf_token = $("input").val();
     const res2 = await agent
@@ -310,7 +310,7 @@ class AtCoder implements XSite {
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res2.status}`);
+    acts.channel.appendLine(`-> ${res2.status}`);
 
     // check login
     if (res2.text.indexOf(`ようこそ、${this.username} さん。`) < 0) {
@@ -320,25 +320,25 @@ class AtCoder implements XSite {
 
   public async getTestAsync() {
     // show channel
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.taskurl: ${this.taskurl}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.username: ${this.username}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.password: ********`);
+    acts.channel.appendLine(`atcoder.taskurl: ${this.taskurl}`);
+    acts.channel.appendLine(`atcoder.username: ${this.username}`);
+    acts.channel.appendLine(`atcoder.password: ********`);
 
     // get agent
     const agent = superagent.agent();
 
     // login get
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.login_get:`);
+    acts.channel.appendLine(`atcoder.login_get:`);
     const res1 = await agent
       .get(this.loginurl)
       .proxy(acts.proxy)
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res1.status}`);
+    acts.channel.appendLine(`-> ${res1.status}`);
 
     // login post
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.login_post:`);
+    acts.channel.appendLine(`atcoder.login_post:`);
     const $ = cheerio.load(res1.text);
     const csrf_token = $("input").val();
     const res2 = await agent
@@ -353,7 +353,7 @@ class AtCoder implements XSite {
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res2.status}`);
+    acts.channel.appendLine(`-> ${res2.status}`);
 
     // check login
     if (res2.text.indexOf(`ようこそ、${this.username} さん。`) < 0) {
@@ -361,14 +361,14 @@ class AtCoder implements XSite {
     }
 
     // get task
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.get_task:`);
+    acts.channel.appendLine(`atcoder.get_task:`);
     const response = await agent
       .get(this.taskurl)
       .proxy(acts.proxy)
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${response.status}`);
+    acts.channel.appendLine(`-> ${response.status}`);
 
     // response to test text
     let text = "";
@@ -394,26 +394,26 @@ class AtCoder implements XSite {
 
   public async submitTaskAsync() {
     // show channel
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.taskurl: ${this.taskurl}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.username: ${this.username}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.password: ********`);
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.submiturl: ${this.submiturl}`);
+    acts.channel.appendLine(`atcoder.taskurl: ${this.taskurl}`);
+    acts.channel.appendLine(`atcoder.username: ${this.username}`);
+    acts.channel.appendLine(`atcoder.password: ********`);
+    acts.channel.appendLine(`atcoder.submiturl: ${this.submiturl}`);
 
     // get agent
     const agent = superagent.agent();
 
     // login get
-    acts.channel.appendLine(`[${acts.timestamp()}] login_get:`);
+    acts.channel.appendLine(`login_get:`);
     const res1 = await agent
       .get(this.loginurl)
       .proxy(acts.proxy)
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res1.status}`);
+    acts.channel.appendLine(`-> ${res1.status}`);
 
     // login post
-    acts.channel.appendLine(`[${acts.timestamp()}] login_post:`);
+    acts.channel.appendLine(`login_post:`);
     const $ = cheerio.load(res1.text);
     const csrf_token = $("input").val();
     const res2 = await agent
@@ -428,7 +428,7 @@ class AtCoder implements XSite {
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res2.status}`);
+    acts.channel.appendLine(`-> ${res2.status}`);
 
     // check login
     if (res2.text.indexOf(`ようこそ、${this.username} さん。`) < 0) {
@@ -436,7 +436,7 @@ class AtCoder implements XSite {
     }
 
     // submit task
-    acts.channel.appendLine(`[${acts.timestamp()}] submit_task:`);
+    acts.channel.appendLine(`submit_task:`);
     const code = fs.readFileSync(acts.taskfile).toString();
     const res3 = await agent
       .post(this.submiturl)
@@ -451,12 +451,12 @@ class AtCoder implements XSite {
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res3.status}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] submissionsurl: ${this.submissionsurl}`);
+    acts.channel.appendLine(`-> ${res3.status}`);
+    acts.channel.appendLine(`submissionsurl: ${this.submissionsurl}`);
   }
 
   public browseTask() {
-    acts.channel.appendLine(`[${acts.timestamp()}] taskurl: ${this.taskurl}`);
+    acts.channel.appendLine(`taskurl: ${this.taskurl}`);
     vscode.env.openExternal(vscode.Uri.parse(this.taskurl));
   }
 
@@ -493,17 +493,17 @@ class AtCoder implements XSite {
 
     // login get
     this.loginurl = "https://atcoder.jp/login?continue=https%3A%2F%2Fatcoder.jp%2F&lang=ja";
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.login_get:`);
+    acts.channel.appendLine(`atcoder.login_get:`);
     const res1 = await agent
       .get(this.loginurl)
       .proxy(acts.proxy)
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res1.status}`);
+    acts.channel.appendLine(`-> ${res1.status}`);
 
     // login post
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.login_post:`);
+    acts.channel.appendLine(`atcoder.login_post:`);
     const $ = cheerio.load(res1.text);
     const csrf_token = $("input").val();
     const res2 = await agent
@@ -518,7 +518,7 @@ class AtCoder implements XSite {
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res2.status}`);
+    acts.channel.appendLine(`-> ${res2.status}`);
 
     // check login
     if (res2.text.indexOf(`ようこそ、${this.username} さん。`) < 0) {
@@ -527,14 +527,14 @@ class AtCoder implements XSite {
 
     // get language ids
     this.submiturl = `https://atcoder.jp/contests/${this.contest}/submit`;
-    acts.channel.appendLine(`[${acts.timestamp()}] atcoder.check_valid_language_ids:`);
+    acts.channel.appendLine(`atcoder.check_valid_language_ids:`);
     const response = await agent
       .get(this.submiturl)
       .proxy(acts.proxy)
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${response.status}`);
+    acts.channel.appendLine(`-> ${response.status}`);
 
     const $submitpage = cheerio.load(response.text);
     const languageIds = $submitpage(`#select-lang-${this.task} select.form-control`)
diff --git a/src/xsite/Yukicoder.ts b/src/xsite/Yukicoder.ts
index d2094f5..91fa68e 100644
--- a/src/xsite/Yukicoder.ts
+++ b/src/xsite/Yukicoder.ts
@@ -125,27 +125,27 @@ class Yukicoder implements XSite {
 
   async loginSiteAsync() {
     // show channel
-    acts.channel.appendLine(`[${acts.timestamp()}] yukicoder.apikey: ********`);
+    acts.channel.appendLine(`yukicoder.apikey: ********`);
   }
 
   async getTestAsync() {
     // show channel
-    acts.channel.appendLine(`[${acts.timestamp()}] yukicoder.problemnourl: ${this.problemnourl}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] yukicoder.apikey: ********`);
+    acts.channel.appendLine(`yukicoder.problemnourl: ${this.problemnourl}`);
+    acts.channel.appendLine(`yukicoder.apikey: ********`);
 
     // get agent
     const agent = superagent.agent().set("accept", "application/json").set("Authorization", `Bearer ${this.apikey}`);
 
     // get file list
     let fileiurl = `${this.api_problemidurl}/file/in`;
-    acts.channel.appendLine(`[${acts.timestamp()}] yukicoder.fileinurl: ${fileiurl}`);
+    acts.channel.appendLine(`yukicoder.fileinurl: ${fileiurl}`);
     const resfilei = await agent
       .get(fileiurl)
       .proxy(acts.proxy)
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${resfilei.status}`);
+    acts.channel.appendLine(`-> ${resfilei.status}`);
 
     // get file
     let text = "";
@@ -156,7 +156,7 @@ class Yukicoder implements XSite {
 
       // get response
       let fileixurl = `${this.api_problemidurl}/file/in/${fileix}`;
-      acts.channel.appendLine(`[${acts.timestamp()}] yukicoder.fileiurl-${nx}: ${fileixurl}`);
+      acts.channel.appendLine(`yukicoder.fileiurl-${nx}: ${fileixurl}`);
       const resfileix = await agent
         .get(fileixurl)
         .proxy(acts.proxy)
@@ -165,7 +165,7 @@ class Yukicoder implements XSite {
         });
 
       let fileoxurl = `${this.api_problemidurl}/file/out/${fileix}`;
-      acts.channel.appendLine(`[${acts.timestamp()}] yukicoder.fileourl-${nx}: ${fileoxurl}`);
+      acts.channel.appendLine(`yukicoder.fileourl-${nx}: ${fileoxurl}`);
       const resfileox = await agent
         .get(fileoxurl)
         .proxy(acts.proxy)
@@ -183,14 +183,14 @@ class Yukicoder implements XSite {
 
   async submitTaskAsync() {
     // show channel
-    acts.channel.appendLine(`[${acts.timestamp()}] yukicoder.problemnourl: ${this.problemnourl}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] yukicoder.apikey: ********`);
+    acts.channel.appendLine(`yukicoder.problemnourl: ${this.problemnourl}`);
+    acts.channel.appendLine(`yukicoder.apikey: ********`);
 
     // get agent
     const agent = superagent.agent().set("accept", "application/json").set("Authorization", `Bearer ${this.apikey}`);
 
     // submit task
-    acts.channel.appendLine(`[${acts.timestamp()}] yukicoder.api_submiturl: ${this.api_submiturl}`);
+    acts.channel.appendLine(`yukicoder.api_submiturl: ${this.api_submiturl}`);
     const code = fs.readFileSync(acts.taskfile).toString();
     const res3 = await agent
       .post(this.api_submiturl)
@@ -201,12 +201,12 @@ class Yukicoder implements XSite {
       .catch(res => {
         throw `ERROR: ${acts.responseToMessage(res)}`;
       });
-    acts.channel.appendLine(`[${acts.timestamp()}] -> ${res3.status}`);
-    acts.channel.appendLine(`[${acts.timestamp()}] submissionsurl: ${this.submissionsurl}`);
+    acts.channel.appendLine(`-> ${res3.status}`);
+    acts.channel.appendLine(`submissionsurl: ${this.submissionsurl}`);
   }
 
   browseTask() {
-    acts.channel.appendLine(`[${acts.timestamp()}] taskurl: ${this.api_problemidurl}`);
+    acts.channel.appendLine(`taskurl: ${this.api_problemidurl}`);
     vscode.env.openExternal(vscode.Uri.parse(this.problemnourl));
   }