Optimization Viewmodes comes out empty when previewing mobile. This started happening after I downloaded UE 4.22. The screenshots shown are taken a few seconds apart in the same project and scene.
What also happened, which I can’t replicate or take a screenshot of is, I somehow managed to get Shader Complexity viewmode turned on, but not working. At first glance it was working, but… everything was weird. After a lot of confusion and testing I realised that it was outputting a complexity heatmap based on output colour. Having an unlit material with a static output of black showed it to be free complexity wise, grey output was red and white was, well, white. The graph also consistently showed the vertex complexity to be 1,5-2 times more than the pixel complexity.