It seems that commas are no longer permitted in set def file names. We have a few problem sets with names like `setSection_5-1,5-2.def`, and several things no longer work unless I rename the file to be like `setSection_5-1_5-2.def`. Specifically what I've noticed is that I can't import the set or download the file. If I rename the file to not use the comma, then I can't rename it back to using a comma.
Was denying commas in set defs an intentional decision? If there is a good reason to do so, then OK. But it seems like commas would be useful enough in set names to warrant their support. In addition to examples like the above, you might have names like `setMean,_Median,_and_Mode.def`, where a comma is natural.