Files with duplicate (possibly empty) header values don't display correctly

[qqmyers]

Files such as
Column 1,,,Column 3
1-1,1-2,1-3,1-4
2-1,2-2,2-3,2-4
3-1,3-2,3-3,3-4
4,5,6,7
appear to be parsed OK by the Papaparse library but they are displayed with only the last column with the duplicate header name (in this case an empty value):

Dataverse does flag these files during ingest and doesn't replace them with .tab files, but it might still be worthwhile to fix or note this issue in the previewer (so users don't think data is missing from the original file). One option might just be to munge names, e.g. replace empty with '' and duplicates with '', etc. Other options might be to just flag the error, flip to not using headers, etc.