Thanks for hint, but I don't want to change preview.
Besides - its just for me, I just need new avatar. Old one drives me crazy, and this annonymous mask works pretty well on other portals so... until I will make new one this will do the job.
Later I will delete this entry.
If you change the preview image on the old submission to be avatar-sized, you can use that as your avatar without making an unnecessary duplicate.
Cool avatar and theme.