The application card and iframe card from ArcGIS Hub display the error message "Missing translation" along with a TypeError for the locale "en." This occurs when adding a web experience that includes a Dashboard embedded with its URL, as well as the 'arcgis-auth-origin' and 'arcgis-auth-portal' parameters.
After executing the provided reproduction steps across multiple environments, the reported error could not be reproduced. Embedding the Web Experience using both the application card and iframe widgets in ArcGIS Hub was tested, and in all cases, the content rendered as expected with no relevant error messages encountered.