Cloud App in iOS 10.3+ gets stuck in full screen preview mode when clicking on a link within an HTML file

Number:rdar://31674886 Date Originated:
Status:Open Resolved:
Product:iCloud + iOS 10.3 Product Version:iOS v10.3, v10.3.1, v10.3.2 Beta 3
Classification:Hang Reproducible:Always
Issue seen in iOS versions 10.3, 10.3.1 & 10.3.2 Beta releases. When iCloud drive contains some HTML files with <a href=.. > anchor tags, on clicking the link, instead of opening Safari browser iCloud App enters full screen preview mode and cannot exit out with the usual gestures (tripple tap to exit fullscreen). The only way to get out of this state is to kill the iCloud app.

Steps to Reproduce:
1. Upload attache Test.html to iCloud account
2. Configure iCloud account on an iOS 10.3 Simulator OR a 10.3 iOS device
3. Browse to HTML file with <a href...> tag link and click the link

Expected Results:
iCloud App must launch Safari App with the target URL in the HTML anchor tag

Actual Results:
iCloud App enters full screen preview mode for the HTML file without navigating to the intended target URL. No actions can be performed on the App once this state is entered, resorting to killing the iCloud app to exit.

iOS v10.3, v10.3.1, v10.3.2 Beta 3

Issue is reproducible on iOS 10.3+ for even a simple HTML file containing a standard link via an anchor tag. Prior to 10.3 Safari browser would get launched.

Attachment: Test.html content:
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "">
Simple HTML with Anchor tag link
<a href="">Link to Google</a>


Please note: Reports posted here will not necessarily be seen by Apple. All problems should be submitted at before they are posted here. Please only post information for Radars that you have filed yourself, and please do not include Apple confidential information in your posts. Thank you!