I am wondering whether it makes sense to keep adding more "layout" options to CSS, given that we have the legacy floats and then the modern flexbox and grid layout. If there are still cases that are not covered, perhaps a better solution to to have one final constraints-based system that covers all layout cases, even if it comes at the cost of complexity. The CSS frameworks and utility libraries will then be built on top of it to provide the next generation of "masonry" grid, etc.