diff --git a/extensions/vscode-web-playground/src/memfs.ts b/extensions/vscode-web-playground/src/memfs.ts
index 40d055a6af37943d349c87a21cb66a3f44962922..e11febc6d0d01124afa4629d21833dd9c45599f0 100644
--- a/extensions/vscode-web-playground/src/memfs.ts
+++ b/extensions/vscode-web-playground/src/memfs.ts
@@ -81,10 +81,7 @@ export class MemFS implements FileSystemProvider, FileSearchProvider, TextSearch
 
 	constructor() {
 		this.disposable = Disposable.from(
-			workspace.registerFileSystemProvider(MemFS.scheme, this, {
-				isCaseSensitive: true,
-				isReadonly: true,
-			}),
+			workspace.registerFileSystemProvider(MemFS.scheme, this, { isCaseSensitive: true }),
 			workspace.registerFileSearchProvider(MemFS.scheme, this),
 			workspace.registerTextSearchProvider(MemFS.scheme, this)
 		);