Export of usages/instances/annotation results is not UTF-8

[pagelj]

Currently, the CSV files that can be downloaded in the frontend replace all non-ASCII characters with question marks.
The file downloader that is used is https://github.com/kennethjiang/js-file-download and is for example called here:

phitag/frontend/lib/service/phitagdata/PhitagDataResource.ts

Line 101 in d2a2ef0

fileDownload(res.data, 'usages.csv');

The solution from the issue kennethjiang/js-file-download#56 (fileDownload(res.data, "usages.csv", "text/csv;charset=utf-8", "\uFEFF")) didn't work for me.

Maybe search for another plugin to handle downloads?