This doesn’t seem to be possible anymore in Specify 7.7 and was fairly handy. We would like to see it return.
We have discussed this internally as well. It was removed due to the drag and drop component relying on outdated code that was not accessibility-friendly. In order to move towards WCAG 2.1 compliance, it was removed in 7.7.
Our programmer Max has made a GitHub issue to restore this functionality. I have added your name as a requestor and moved it up in priority.