diff --git a/.eslintignore b/.eslintignore
index 8ca6e026..d2fabcea 100644
--- a/.eslintignore
+++ b/.eslintignore
@@ -1,3 +1,4 @@
 venv
 .venv
-standalone_app
\ No newline at end of file
+standalone_app
+vscode
\ No newline at end of file
diff --git a/package.json b/package.json
index 9c214ab9..5b5d301a 100644
--- a/package.json
+++ b/package.json
@@ -5,10 +5,10 @@
   "description": "Dashboard for Optuna",
   "main": "index.js",
   "scripts": {
-    "fmt": "biome format --write . && biome check standalone_app --apply",
+    "fmt": "biome format --write . && biome check standalone_app vscode --apply",
     "lint": "npm run lint:eslint && npm run lint:biome",
     "lint:eslint": "eslint . --ext .ts,.tsx --max-warnings 0",
-    "lint:biome": "biome format . && biome ci standalone_app",
+    "lint:biome": "biome format . && biome ci standalone_app vscode",
     "watch": "NODE_ENV=development TYPESCRIPT_LOADER=esbuild-loader webpack --watch",
     "build": "webpack",
     "build:dev": "NODE_ENV=development TYPESCRIPT_LOADER=esbuild-loader webpack",
diff --git a/vscode/src/web/extension.ts b/vscode/src/web/extension.ts
index 914f35ba..270e4866 100644
--- a/vscode/src/web/extension.ts
+++ b/vscode/src/web/extension.ts
@@ -5,7 +5,7 @@ export function activate(context: vscode.ExtensionContext) {
     'Congratulations, your extension "optuna-dashboard" is now active in the web extension host!'
   )
 
-  let disposable = vscode.commands.registerCommand(
+  const disposable = vscode.commands.registerCommand(
     "optuna-dashboard.openOptunaDashboard",
     async (fileUri: vscode.Uri) => {
       // In VS Code, the path separator of fileUri is always '/'
@@ -30,15 +30,17 @@ export function activate(context: vscode.ExtensionContext) {
       const appPath = panel.webview.asWebviewUri(indexJsUri)
 
       panel.webview.html = getWebviewContent(appPath)
+      // biome-ignore lint/suspicious/noExplicitAny: <explanation>`
       panel.webview.onDidReceiveMessage(async (message: any) => {
         switch (message.type) {
-          case "webviewDidLoad":
+          case "webviewDidLoad": {
             const storageContentBase64 = await readFileAsBase64(fileUri)
             panel.webview.postMessage({
               type: "optunaStorage",
               content: storageContentBase64,
             })
             break
+          }
         }
       })
     }
@@ -55,9 +57,7 @@ async function readFileAsBase64(uri: vscode.Uri): Promise<string> {
 
 function uint8ArrayToBase64(uint8Array: Uint8Array): string {
   const binString = Array.prototype.map
-    .call(uint8Array, function (ch) {
-      return String.fromCharCode(ch)
-    })
+    .call(uint8Array, (ch) => String.fromCharCode(ch))
     .join("")
   return btoa(binString)
 }