When you add the image, you can choose between a few different representations in the bookmark popup.
I don't think we have any way for site owners to specify exactly what they want though. Also don't think any sites would really use it.
Thanks for your reply and the clarification!
Indeed, the 126.96.36.199 is PPAPI and 188.8.131.52 is NPAPI. As I understand it, I have been using all this time dangerous and outdated version 15 of the plugin. However, shouldn't Opera automatically block the plugin and forbid me using it unless I'd update it?