There are a few ways to post a Bio pic. This site doesn't make it easy. Makes ya wonder if they frown upon it.
When you right click on a site Bio pic there is no drop downs.
In this case take a screenshot of the Bio pic you want.
Then go to any image posting site and upload your screenshot.
Then right click on your pic and choose the 'Copy image address' from the drop downs.
Then come back here and in the Reply to Thread box, click on the 'Insert Image' yellow icon at the top of box.
Then in the drop down box that appears paste in the URL you copied from the image posting site.
Works like a charm like this below: