After using that feature for around 30 minutes on and off I suddenly noticed an inversed-looking Tiny Thor in the background of my text editor. I was very confused, so I moved the window around and discovered that the sprite was "burned" into my display over all applications, even after turning the display and the system on and off.
Here is a short video I took: https://youtu.be/oJHUqmtO6Gw
Seems like I have to do a softer effect on it if I don't want to destroy my display...
BTW: After turning the display off over night my lovely Tiny Thor vanished away. I'm missing him.... ;)