[Inkscape-user] Reporting Inkscape crash - howto?

Hi, I'm on Ubuntu 16.04 64 bit and Inkscape is very crashy. I even moved to the stable PPA packages and it's the same.

Could someone point me to where I can best make a bug report?

The error seems to be:

** (inkscape:9729): CRITICAL **: void sp_ruler_remove_track_widget(SPRuler*, GtkWidget*): assertion 'SP_IS_RULER (ruler)' failed

** (inkscape:9729): CRITICAL **: void sp_ruler_remove_track_widget(SPRuler*, GtkWidget*): assertion 'SP_IS_RULER (ruler)' failed *** Error in `inkscape': double free or corruption (fasttop): 0x0000000004971570 ***

It happens on exit from Inkscape.

Thx, /d