Re-ordering variants of an image doesn't work properly when working with smart albums

When working with smart albums (as I do most of the time) and attempting to re-order variants of an image by drag and drop the order of the variants doesn't change, only the numbering of the variants changes (correctly). When I collapse the group of variants and re-open it (or leave the smart album and re-enter) the order of the variants is correct and according to its numbering. This only happens with smart albums! I don't know with which version this error occurred for the first time, but I know for sure that it worked in 15.x < 15.3. and it works correctly in the Mac version.
Has someone a solution? I put in a ticket but nothing happend up to now.