I don't know what happened as my computer timed out - hence the double post and incomplete answer. What I was going to continue with is if you just want to post an image in a message, first right click on the image and choose "Copy image address". Then within this editor, click the "Insert image" icon (hover over the icons to see which one it is). When you do so, two bracketed icons appear in the message then paste the "image address" between them.
