Matt,
If you look at Geocoder Widget for example and you click in the geocoder box and start typing using the 10 key then move your mouse over the map but not over the widget then it pans the map and does not input numbers into the geocoder.
The geocoder widget is the one that is available in the Web appbuilder by default. The current default settings for that widget require it to have at least one locator in the drop down and no way to combine them all into a single search option. I am using the Developer edition, however I do not get the same results when using WAB from AGOL.
Let me know if you need more information to pin point this.
Thanks
-Stan