Version: platform 8530.11.0, multiple chrome devices.
OS: ChromeOS 53.0.2785.13

What steps will reproduce the problem?
(1) Launch the "AIRSecureTest" kiosk app, manually or auto-launched.
The webstore id is "hblfbmjdaalalhifaajnnodlkiloengc".
(2) Click on "Go to Practice Test Site", and sign in as GUEST.
(3) Select a grade level (any will do).
    Select any test.
    Select the default Settings.
    Select "Yes, Start My Test".
    Yes, the audio test works.
    Click on "Begin Test Now".

What is the expected output?
At this point the user is supposed to be able to zoom in (ctrl+), zoom out (ctrl-), and return to normal view (ctrl0).  

What do you see instead?
Initially you can only zoom in.  Once you have zoomed in, you can only zoom out as many times as you zoomed in before.  Return to normal view (ctrl0) is apparently ignored.

This application was republished back in Dec. 2015, and the user interaction has definitely changed from what the original test case described [Kiosk test: App compatibility, case 1.5.2].  I am uncertain whether the view-behavior is a bug, or perhaps a "feature" of the new version of the App?

I will execute the same test case on a M52 build to see its behavior there.

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