UserAgent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.115 Safari/537.36

Steps to reproduce the problem:
1. Go to this fiddle: https://jsfiddle.net/KanaScott/b39h26Ln/ (or any number-type input box that does something non-interactive on change).
2. Click the up arrow repeatedly (or down, once the number is higher) WITHOUT moving your mouse once you've started clicking. Do not alter the number using keyboard arrows.
3. Once the problem is observed, move your mouse off the arrows.

What is the expected behavior?
The number below the input box should change every time the arrow is clicked, regardless of mouse position.

What went wrong?
Instead, the number below the input box changes on the first click only, and then only after moving the mouse away from the arrows does it change to whatever number was reached.

Did this work before? Yes Unsure, sorry!

Chrome version: 59.0.3071.115  Channel: stable
OS Version: 6.1 (Windows 7, Windows Server 2008 R2)
Flash Version: 

I swear this worked literally last night, and that I would have noticed it not working! If you change the input box with the keyboard arrows it works fine. Firefox 54.0.1 has no problem.