This is a very beta version of the separate functions I use to generate srcset/bgset markups. There's some similar functions floating around in the forum but this one is a bit different because you can set "named image sets" which you can use easily site-wide. It's definitely work-in-progress so use it at your own risk. MarkupSrcSet Generate srcset and bgset markup for lazysizes. Features generate srcset/bgset markup for lazysizes set image sizes in JSON array add required JavaScript