A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
Yeah, I think there is a bug in desktop also. In desktop, if you right click and do Select Data again, and then just click OK, it matches the SharePoint version. However, you gave me an idea that I just tested and it worked. Apparently, if you unhide row 9, then reset the chart, it's resolved. Not sure why, but maybe it has to do with the fact that rows hidden affect the filtering, so it gets confused with the categories hidden as well.