diff --git a/.vscode/tasks.json b/.vscode/tasks.json
index aa6c648e..36cf472e 100644
--- a/.vscode/tasks.json
+++ b/.vscode/tasks.json
@@ -4,7 +4,7 @@
     {
       "type": "shell",
       "command": "npm",
-      "args": ["run", "build", "--", "--sourcemap"],
+      "args": ["run", "build:debug"],
       "label": "build",
       "presentation": {
         "clear": true,
diff --git a/fixtures/demo/tsconfig.json b/fixtures/demo/tsconfig.json
index d6d62cc4..6dfc0ed8 100644
--- a/fixtures/demo/tsconfig.json
+++ b/fixtures/demo/tsconfig.json
@@ -2,7 +2,7 @@
   "compilerOptions": {
     "checkJs": true,
     "jsx": "react-jsx",
-    "lib": ["es2020"],
+    "lib": ["dom", "es2020"],
     "module": "node16",
     "strict": true
   }
diff --git a/package.json b/package.json
index 8704b5fa..0cccae17 100644
--- a/package.json
+++ b/package.json
@@ -29,16 +29,19 @@
   ],
   "scripts": {
     "build": "esbuild @mdx-js/language-client @mdx-js/language-server --bundle --platform=node --target=node16 --external:vscode --outdir=out",
+    "build:debug": "npm run copy-libs && npm run build -- --sourcemap",
+    "copy-libs": "cpy 'node_modules/typescript/lib/lib.*.d.ts' out/",
     "format": "remark . -qfo && prettier . -w --loglevel warn && xo --fix",
     "start": "npm --workspace @mdx-js/monaco-demo run start",
     "test-api": "npm run test-api --workspaces --if-present",
     "test": "npm run build && npm --workspaces run build && npm run format && npm run test-api",
-    "vscode:prepublish": "npm run build -- --minify"
+    "vscode:prepublish": "npm run copy-libs && npm run build -- --minify"
   },
   "devDependencies": {
     "@changesets/changelog-github": "^0.4.0",
     "@changesets/cli": "^2.0.0",
     "@types/react": "^18.0.0",
+    "cpy-cli": "^4.0.0",
     "esbuild": "^0.16.0",
     "ovsx": "^0.7.0",
     "prettier": "^2.0.0",