Support for Base64 content from object

When working with Native, it is normal to generate images in Base64 format (e.g. Signatures) and store this Base64 encoded image in a String attribute.  It would be good to be able to display these Base64 images in the web UI without having to convert to a File.  As far as I can see this widget only works with remote content.  Could it be made to display content directly from an object? 