One-time setup needed before this copy can be used.
This file is set up for a shared, multi-user cloud database (Firebase), but the connection details haven't been filled in yet.
Open SETUP-GUIDE.txt (downloaded alongside this file) and follow the steps to create a free Firebase project, then paste your project's config into the FIREBASE_CONFIG object near the top of this file's code (search for YOUR_API_KEY_HERE).
Once that's done, reload this page.