Board Thread:Game Discussion/@comment-15491722-20131209070003/@comment-10782738-20131210210345

They changed the size of the avatar square in one of their updates. Before that "update" all allied seeds would have an extra few pixels around the image to allow you to see the blinking. Now like GOC said, you can only see that on transparent images. I don't see them changing that ever again. However, if you want your allies to know it's you, I recommend (if you're able to) creating or finding an image with a transparent background and uploading that.

If creating an image in a photo editing program, make sure to save it as a PNG file so the transparency is preserved. JPG is unable to display transparent images.