This is a very strange glitch I found, I tried to record it as a gif but the constrained fps made it not show up but I recorded the screen: https://mtc.cdn.vine.co/r/videos/BE263F59B91219323643163983872_2f49a80283e.2.1.11630754882517266564.mp4?versionId=5vw6Wp1o6WNWkIMy13ZSjg9KCx16lZZN
Saturated colors are randomly blinking.
This is the post processing material setup:
Without the Lerp the glitch does not occur. The Scalar Parameter is also important. Using just a constant makes the glitch not occur either. This is a setup to get just lighting which works with simple diffuse materials. I noticed that without the desaturation I get black lighting where the the base color is very saturated, that black occurs when I put the result in a cheap contrast node or desaturate that. So there might be another bug/glitch here.
P.S.
I would have used a static switch instead of Lerp but that is currently bugged, at least with post processing materials.