NPE when uploading a new image via xinha and selecting it

1. Open a document with a xinha field
2. Click 'Insert/modify' button
3. Choose a new image by clicking on browse, then upload it
4. The 'Size' dropdown in this dialog reads 'Choose one', and even after selecting the newly uploaded image it does not turn to 'Original' nor 'Thumbnail'
5. If you press OK in this case you get a NPE (in UI nothing happens)