I noticed a (new? or never before noticed) button in the processors tab: mouse cross.
The reason I found it was because I had a green outline and some strange small line in one of my outputs. I switched off all layers and scenes a it still was there. Loaded a different project and it was not there. Digged deeper into the project where it was appearing and found it.
Can someone tell me the use of the mouse cursor? And would it be an idea to switch it off when ON AIR is activated?