When I open the “Editor”, often this message “Function…” appears and keeps floating over my screen even after minimizing the canvas! This is annoying and also a problem because often I take screenshots of my canvases and this message gets in my way!
I tried also to turn off the Gui.Tooltip but I did not find a way. In any case these tooltips appear when the mouse cursor stays for some time on GUI element. If you move the mouse cursor away it disappears. So it is easy to make it disappear. @bellenot can tell you more when he will be back.
I usually keep moving the mouse a lot and it seems that it’s almost impossible to get rid of it. But, once in a while it seems to disappear… but randomly… and comes back eventually.