- Go to demo and open Pages-app
- Create a page and export it (by default, it is a yaml file)
- Remove the page
- Try to import the page
- Check it fails with the message "An unsupported upload file type"
The page can be imported
The upload is aborted and the message "An unsupported upload file type" is displayed
When removing the allowedMimeTypePattern restriction from the dialog we found the upload to detect the file as application/octet-stream