Clicking quickly on the x/y width/height spinbox causes them to get stuck increasing/decreasing the value

Problem:
With something selected, clicking quickly on the x/y width/height spinbox causes them to get stuck increasing/decreasing the value until the background is clicked. If another object is clicked that object will now have its x/y width/height value stuck increasing/decreasing instead.

Steps to reproduce:
1. Draw a box or other element on the page
2. Select the object with the select tool
3. Click on the increase/decrease arrows for the x/y width/height inputs on the top bar quickly and that option will get stuck on

Version tested with:
Inkscape 0.91 r13725 (from ubuntu 16.04 repos)