Default Bookmark in SAP Analytics Cloud / Analytics Application

I set up bookmark functionalities and tried leveraging the "isDefault" flag as shown here in the Analytics Designer API Reference Guide.

However a "default" bookmark does not load when opening the application.

When loading the "default" bookmark in the "OnInitialization" Script, the Application goes into a loop as it's initializing again when applying the bookmark.

So my Question is: How was the default bookmark intended to work ?