webstudio/apps/designer/app/shared/tree-utils/clone-instance.ts

import ObjectId from "bson-objectid";
import produce from "immer";
import { type Instance } from "@webstudio-is/react-sdk";

const updateIds = (instance: Instance) => {
  instance.id = ObjectId().toString();
  for (const child of instance.children) {
    if (typeof child === "string") continue;
    updateIds(child);
  }
};

export const cloneInstance = (instance: Instance): Instance =>
  produce(updateIds)(instance);