Crash on deleting an element being dragged
Came from a crash reporter.
1) Start dragging an element (e.g. dynamics, but this is reproducible with other elements too).
2) While holding left mouse button, press Delete.
3) Continue dragging, or just release mouse button.
This is reproducible since 3.1.0 version, 3.0.5 seems to be unaffected by this.