Hi people Suddenly I noticed my scene was responding very slowly and its size increased from less than Imb to 70Mb. I found out the culprit : in the Out network, the “mantra_ipr” had been duplicated more than 700 times. In the edit menu, I noticed a lot of items called “auto create ipr rop”. Deleting all these nodes took forever. So what does create automatically IPR rop's? The render region? Thanks Gz