Xinha image url duplicates when saving and then toggling the source button

The steps to repreduce:

1. Add an image in the Xinha field with the image picker
2. Save document
3. click on the Xinha field to enable it again.
4. Toggle the (html) source button

The image disappears when toggling the source button, when you see the source you can see the url of the image is somehow duplicated.