On reboot Adobe CC attempts to download 'cc.png' from 'connect.ffc.adobeoobe.com'. I've been pressing cancel hoping an update would fix the issue but no luck so far. There is another thread with the same issue but that was marked 'solved' when it was clearly not solved.
Also I should mention this website's 'insert image' function is bugged. If I try to upload the screenshot file I did for this topic as the filename 'Annotation 2019-11-08 170529.png' I get the error 'HTML detected' and the image gets deleted from the post. But once I rename the file on my PC and reupload it as 'Annotation 20191108.png' the html detector doesn't complain.
Go to the forum to report bug get held up because of a forum bug. Really doesn't inspire confidence.
I just started having the same exact issue less than a week ago. I felt like living on the edge one day and opening it, and it's just a long horizontal bar, like a separator or divider bar, so I don't think there's anything malicious about it...it's more annoying than anything.