support "@types" in treeshaker

build/lib/standalone.ts

@@ -55,6 +55,13 @@ export function extractEditor(options: tss.ITreeShakingOptions & { destRoot: str
 	// Take the extra included .d.ts files from `tsconfig.monaco.json`
 	options.typings = (<string[]>tsConfig.include).filter(includedFile => /\.d\.ts$/.test(includedFile));
 
+	// Add extra .d.ts files from `node_modules/@types/`
+	if (Array.isArray(options.compilerOptions?.types)) {
+		options.compilerOptions.types.forEach((type: string) => {
+			options.typings.push(`../node_modules/@types/${type}/index.d.ts`);
+		});
+	}
+
 	let result = tss.shake(options);
 	for (let fileName in result) {
 		if (result.hasOwnProperty(fileName)) {