Chart disappearing

Hi,

A chart on my calc sheet disappeared after save to ODF:

I can upload a picture of the chart before saving the file (i exported it).

After file reopen, the chard data is empty, no data series.

Is there a way to enable logging? Maybe some assert print or debug print would be useful, maybe the some parser failed… I saw the debug page, but for GDB use i would need to read the code for charting.

Is this a bug?