The window comes up fine, but when I click “add” nothing happens. I’ve tested on both Firefox and Chrome.
I’ve also tested adding a column to one of my own private courses and that worked fine. Though the course is much smaller. So is this a thing where contributors can’t add columns or is it because this course has a large database?
I can add an extra column if you like. If you leet me know whether this should be a regular column or an attribute column, along with the column’s desired title and any non-default settings you’d like to add, I’ll take care of it asap.