The same layout, with identical heights, renders differently on Safari, IE, and Edge than it does in Firefox and Chrome. Since all the columns/rows are of identical height (or 2x height/width), the layout should retain it's original order, but it does not.
For a live example of this, see:
https://www.loungelizard.com/work/
This issue also occurs on Isotope, even with the "original order" flag set.