UserAgent: Mozilla/5.0 (X11; CrOS x86_64 8737.1.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2837.0 Safari/537.36
Platform: 8737.1.0 (Official Build) dev-channel candy

Steps to reproduce the problem:
1. Open an app set to 'open in window'
2. Try to minimize the window via window buttons
3. 

What is the expected behavior?
The window should minimize

What went wrong?
Nothing happens

Did this work before? N/A 

Chrome version: 54.0.2837.0  Channel: dev
OS Version: 8737.1.0
Flash Version: Shockwave Flash 23.0 r0

The main tabbed browser window works fine, it's only effecting single app windows, and some popups that use a single page window. These windows can still be closed by right-clicking on the tray icon, or from the overview screen.