Dashboard

See: https://9to5mac.com/2019/06/04/dashboard-in-macos-10-15-catalina/

including the following from that link:

Many features of Dashboard can now be accessed via the Today tab in Notification Center on the Mac. Here, you can add widgets for various applications like Reminders, Calendar, weather, stocks, and more. It also integrates with third-party applications

All the widgets are gone. Now you can only add "apps" to the Today-tab. When browsing through the app-store the purpose of this change becomes brutally clear - revenue. Over 90 % of the apps that Apple propose are at a cost. The previous Widget solution was more based on free and donation options.

Getting tired of Apples greedy fingers.

Dashboard is an idea that came and is now gone. Mojave had Dashboard but it didn't start up by default.