Last year we made a solution for a customers website (on a linuxserver). They also have a sharepointserver, where they update some numbers daily in an excel sheet, and use a macro to generate a public csv from those numbers. Then we had a small pythonscript on the (linux) webserver that downloaded the csv and generated a svg.
This has worked fine until about a week ago, when the sharepoint server suddenly started returning a html file instead of a csv. Earlier, if I tried going to the address of the csv, my browser asked if I wanted to download the csv file, but now I get a "Excel Online"-spreadsheet, where also some of the cells are wrong (seems the csv gets messed up because excel misunderstands the delimitors). The customer is pretty sure nothing was changed by them.
I am really out of my element with the excel/sharepoint-part, so - does anyone have some idea what is wrong or if something was changed by MS/sharepoint lately that could explain the change in behaviour?