Right now it's just an attached thumbnail that one can click on to see the larger version. I right clicked on it, opened it in a new tab, then copied the URL, then back here to click on the postcard icon and paste address in it.
No, in your orginal post, where you have uploaded your attachment, right click on the attachment name (which is under the text box). Then open up a new tab with your pic in it. Copy the URL, come back to other tab where you are posting.....click on the postcard/picture icon, and paste the URL in there.
Then click ok, and the pic will show up in the post. The attachment will still also show, unless after uploading the pic into a post and getting the URL.....you delete that post and just do another with the URL pasted as described.
I mostly use Photobucket.......it's free to upload pics to, and then easy to post pics here.