Hey @cmartin, your issue is duplicate of issue described here:
It seems this is bug with new xCode 10 and when keyboard appears, layout constraints are broken, which messes up event selectors on web page. I dont think there is still good solution to this issue. I have tried many things but still seeking for solution.
Current solution is to build your app with xCode 9 . That way you wont have those issue. Sooner or later Apple will block xCode 9 from building apps, so we definitely need some fix soon