FYI – as of iOS 10 when focus moves into a dialog the VoiceOver focus gets trapped in the dialog’s title and you can’t swipe out to the rest of the dialog's content with gestures. Explore by touch does allow the user to explore elements on the screen. An example of the situation can be found at the link below: https://labs.ssbbartgroup.com/index.php/ARIA_Dialog_Role
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