Occasionally, when I click the up-arrow to show all items in my taskbar, I can see tens of identical icons as shown below:
They disappear very rapidly, before I can even mouse-over or click them to find out what they are, but I did manage to take this screenshot before they were all gone.
How can I figure out what the cause of them is? None of my running processes or installed programs appear to use this icon. (Or even better, does anyone recognise the icon?)