There is. First get into chat, Next look above the text field. For Options, inside of options click effects, From there you will want to click background and custom, then you upload for background choice and then you have it.
My previous background that I was using, I clicked it off for a moment to see what else I had in my stash and now I can't get my original background that I "liked" back in place. It says on the chat-effect area to use non progressive jpg, whatever that means.