Has anyone overcome this issue?
In a classic UI dashboard, the embedded page widget is working fine for a webcam view of a construction project. Similarly, an embedded weather widget works.

Switching it to Modern UI and it results in a 404 - File or directory not found error. The weather widget has the same result.

Toggling back and forth between classic/modern, the embedded pages work in the classic UI and 404 in the modern UI
Sample webcam URL used for testing:
Sample weather URL: