I had this similar issue earlier, and for some reason I managed it. But now just cannot solve my problem even I checked my earlier page and copied settings but nothing.
It´s about one upcoming page but so far can be seen
I am using Cornerstone, and I have changed Image settings width Max 100% and Columns setting (row) width 100%. But the result nothing. I want only that top banner image to be full width.
ANSWER FOUND!
I needed to change the template in quick edit to Blank - No Container. Maybe there are some other solutions too, but at least for now this looks to work
