Removing --startwhite in Visual Metrics introduced higher deviation in metrics for Chrome

[soulgalore]

I think it's because of Chrome making the orange layer going away step by step, so we can have a frame where x % is still orange. I've made a branch #654 that makes us start white if we don't use preURL/preTask. I'll merge it and release it when I know for sure it helps.

[soulgalore]

Released a fix in 3.11.1