So it is not clear to me how I can help to find the problem in Matplotlib, or adjust my code from a 2.0.2-compatible version to one that works with 2.1.0. (In 2.0.2 I only see a message as below.) ...

Bug report Bug summary When an axis is shared with another its registered "xlim_changed" callbacks does not get called when the change is induced by a shared axis (via sharex=). In _base.py the set ...