Dialogs with text input can get obscured on iOS

(Bug, Investigate , Priority: High, Test Status: No automated tests yet , Reported By Justin du Coeur, )
UX
Summary: There is a well-known bug in the interaction between Bootstrap 3 Modals and iOS' virtual keyboard: when the keyboard comes up, the Model doesn't move accordingly.
See this article for a design of how to fix the problem.
As of this writing, I believe that the only Dialog affected by the problem is Login, and that's small enough for it to not be a serious issue.