How to debug iOS 14 widget in Xcode 12?

I am working on an iOS 14 widget which I would like to my existing iOS 11+ app. The whole process is quite cumbersome because it happens quite often that something does not work as expected.

For example the widget shows unexpected data, or is not rendered as expected (e.g. as described here). I assume that something wents wrong when the system requests the widget and its content from my app extension. However I cannot figure out what this might be.

Is there any way to actually debug the widget extension? Seeing when the code is executed and how it works?

I have already tried to hook up the debugger to the widget extension (using the Debug/Attach to process menu in Xcode). While the process is listed there, the debugger shows no log output nor stops on breakpoints.

Using the system console to show the logs of the iOS simulator devices does not work as well. It does not matter if print(...) or NSLog(...) is used. No output reaches the console.

Select your widget target at the top left corner of Xcode, build and run the app, then the widget process will be able to debug and show logs. (This example project is downloaded provided by Apple: https://developer.apple.com/documentation/widgetkit/building_widgets_using_widgetkit_and_swiftui)