UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36

Steps to reproduce the problem:
1.   install an extension *which paints its' own menu,* for example Adblock Plus, or TamperMonkey.  
2.  visit  chrome://flags/
3.  change setting  #top-chrome-md to "Normal"
3.  change setting  #secondary-ui-md to "Disabled"
4.  restart chrome
5.  click on extension icon in toolbar
6.  observe immediate crash to desktop.

7.  start chrome
8.  click on extension icon in toolbar
9.  observe immediate crash to desktop.

10.  start chrome
11.  visit  chrome://flags/
12.  change setting  #secondary-ui-md to "Default"
13.  restart chrome
14.  click on extension icon in toolbar
15.  observe normal function of extension menu.

What is the expected behavior?
Chrome should not segfault when extensions try to draw their own menus.

What went wrong?
without reading any code, my guess is that the #secondary-ui-md flag, when disabled, moves the browser's drawregion handle into a protected memory space, which leads to a segfault when the extension tries to paint to that region handle.

Crashed report ID: ea92ad2f-4d04-4e8a-9840-4b5f32399f04  bf9e4ab9-cd23-4d67-b370-7b0ce4666e9b  08f59a30-1387-4dc4-9f80-cb009cdf6054

How much crashed? Whole browser

Is it a problem with a plugin? No 

Did this work before? Yes pre "material design"

Chrome version: 69.0.3497.100  Channel: stable
OS Version: OS X 10.13.6
Flash Version: