Pop up on blank screen

I just rebooted my PC (Win 10). I have TV 13 installed (13.2.26558). While the screen was still blank, just a task bar across the bottom, almost no icons on it yet (notably not yet the TV13 icon), a tooltip kind of window appeared in the middle of the black screen. It told me that there was a new version available ... you know, that little tooltip that appears near the download button on the TV main window.. I don't have a problem being told about the update.

The question is - why did that appear? There was no visible window for TV and I had not moved or pressed the mouse. Quite likely that TV is getting itself running in the background but it sure shouldn't be putting anything on the desktop ... should it?