Under the text input area, click on the Attachments tab, then click on the Add files button. (Many different file formats are supported)
I don't find the attachments tab in the text input area. I have a PNG file copied to my clipboard, but no place to paste it. If I right click on the text area a menu comes up with paste as an option, I click on it and nothing happens. What a bonehead must be! Send me a screen shot of what they are talking about here, please.