Online catalog consists of numerous Library templates created and shared by Memento Database community. You can choose one to use as a skeleton and edit it as you wish.
To create a new Library based on the template, choose Add Library option from burger menu at the top-right of the window and tap Online catalog. In the window that will be opened, there is a list of templates you can filter, sort or search in:
Once you find the most suitable one, tap it and click icon to download to your Library collection. The downloaded template can be edited just like the Library you’ve created from scratch.