Chrome Version       : 66.0.3359.181
OS Version: OS X 10.13.4
URLs (if applicable) :
Other browsers tested:
  Add OK or FAIL after other browsers where you have tested this issue:
     Safari: OK
    Firefox: OK
    IE/Edge: OK

What steps will reproduce the problem?
1. make the bookmarks toolbar always visible 
2. create a folder there (call it "test")
3. put 15 or more bookmarks in this folder
4. arrange your Chrome window such that the "test" folder is visible in the main window and not off to the right in the '>>' overflow area
5. command+click on the "test" bookmarks folder to trigger opening all of its bookmarks as tabs
6. a confirmation dialog will appear "Are you sure..." click YES

What is the expected result?

All of your tabs should open!

What happens instead of that?

System plays an error/alert BEEP sound and nothing is opened. Chrome now enters a zombie/unstable state where new tabs that are opened will have difficulty closing (sometimes requiring 2 clicks on the 'x') and the application itself will refuse to Quit cleanly via Cmd+Q. Usually you will need to Force-quit the app at this point.

I discovered 2 alternate code paths that do NOT trigger this very strange bug:

1. If you instead RIGHT-CLICK and choose "Open All" with the mouse, the tabs open and everything works as expected.

2. If you resize (shrink) the window such that the "test" bookmarks folder is positioned in the overflow area (>>) off screen, and then Cmd+click it, everything works as expected.

So, it is something about the folder being visible in the toolbar when triggering the confirmation dialog that is causing things to go pear-shaped.

Screenshots and some minidumps after Chrome crashed are in the attached ZIP.

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

UserAgentString: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/66.0.3359.181 Safari/537.36