I should suggest a new option in the Image tab called “use this image if there is not a Featured image” because im having problems in listings, searches, tags and etc.
It shows a gray-color “empty” background but it works in post and pages.
Using .generate-content-header { background-image: url(); } overwrite all the featured images.
I have all them configured in the same Header but there is no “Featured Image” in those pages. I need to be able to configure a global image to them without override the post and page ones.