The modalview widget shares common code with the Kendo UI web widgets (the popup for the dropdowns, to be more specific), hence the behavior you exhibit. As Iliana already mentioned, Kendo UI Mobile is targeting mobile devices exclusively, and we did not consider this use case as a possible problem for our customers.
If you do not use any of the form widgets in your project (or their popups staying open is not a problem for your case), feel free to comment out the lines you have already discovered.
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