FailedToLaunchAppError: Failed to launch com.example.Scrumdinger

Even though the code is 100% works in the simulator, the preview canvas gets "Cannot preview in this file" error more often. How could I get the issue sorted? The issue is sorted after restarting the xcode several times. I tried to attache the generated report as a zip file, but it does not support to attach.

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We're sorry you're having trouble using previews! We will need the diagnostics Xcode Previews generates in order to make sure we understand the error the previews system is encountering.

If you are having issues with Xcode, macOS, catalyst or on-device iOS previews then download and install the logging profile for your device. Instructions and profiles are available here: https://developer.apple.com/bug-reporting/profiles-and-logs/?name=swift Attach the sysdiagnose to the radar as well as the diagnostics using the instructions below.

Then when you reproduce the problem in Xcode:

  1. Either (a) an error banner will appear, click the "Diagnostics" button in that banner. Or (b) if you’re not seeing an error but you still want to provide diagnostics, you can get the same diagnostics window by going under the Editor menu in the menu bar, then selecting the Canvas submenu, then selecting “Diagnostics”.
  2. In the sheet that appears, click "Generate Report" in the bottom left of the sheet
  3. Attach (or make from the folder) the resulting zip file to the bug (will be named something like previews-diagnostics-0123456789.zip)