Chrome Version       : 66.0.3359.158
OS Version: 10452.85.0

What steps will reproduce the problem?
1. Press Ctrl-Alt-/ to bring up the keyboard shortcut dialog
2. Press Ctrl-Alt-/ again, which closed the old version

What is the expected result?
Keyboard shortcut window closes.

What happens instead of that?
Nothing.

Please provide any additional information below. Attach a screenshot if
possible.

Closing with Ctrl-W would also be fine, but there should really be a way to close this dialog with the keyboard if we can open it that way.

UserAgentString: Mozilla/5.0 (X11; CrOS x86_64 10452.85.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/66.0.3359.158 Safari/537.36