Pasting an HTML <img> does not download the image in the backend but links to the original image URL which is not obvious to the end-user

[silviubogan]

This takes place in:

1. TextBlockEdit
2. HtmlSlateWidget
3. and maybe also in RichTextWidget

Maybe it is more user friendly to download the image inside the backend and use the newly generated URL in the Slate tree.

[tiberiuichim]

I think this problem should be handled only in the TextBlockEdit, where it's obvious what the solution is (upload an image to the nearest possible image container).