Changing #secondary-ui-md to default prevents the crash from occurring, so seems to only occur with the non material secondary UI. 

Can you please attach the Apple crash log and/or the server crash id from chrome://crashes ?

Crash ID: crash/f7f427fce9bfa693

Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Thanks for the crash id.

Changing values in about:flags may cause instability. The top-chrome-md and secondary-ui-md are both enabled by default and will enabled, so I think this is just WontFix (though +elly if they disagree).


Thread 0 (id: 0x73adb6) CRASHED [EXC_BAD_ACCESS / KERN_INVALID_ADDRESS @ 0x00000340 ] 

Stack Quality84%Show frame trust levels
0x0000000119ca2c4d	(Google Chrome Framework -view.cc:2377 )	views::View::UpdateParentLayers()
0x0000000119ca1f56	(Google Chrome Framework -view.cc:218 )	views::View::AddChildViewAt(views::View*, int)
0x000000011ad9dd2b	(Google Chrome Framework -extension_popup.cc:54 )	ExtensionPopup::ExtensionPopup(extensions::ExtensionViewHost*, views::View*, views::BubbleBorder::Arrow, ExtensionPopup::ShowAction)
0x000000011ad9e7b1	(Google Chrome Framework -extension_popup.cc:50 )	ExtensionPopup::ShowPopup(std::__1::unique_ptr<extensions::ExtensionViewHost, std::__1::default_delete<extensions::ExtensionViewHost> >, views::View*, views::BubbleBorder::Arrow, ExtensionPopup::ShowAction)
0x000000011ada1ea5	(Google Chrome Framework -extension_action_platform_delegate_views.cc:94 )	ExtensionActionPlatformDelegateViews::ShowPopup(std::__1::unique_ptr<extensions::ExtensionViewHost, std::__1::default_delete<extensions::ExtensionViewHost> >, bool, ExtensionActionViewController::PopupShowAction)
0x000000011ad9911a	(Google Chrome Framework -extension_action_view_controller.cc:352 )	ExtensionActionViewController::TriggerPopupWithUrl(ExtensionActionViewController::PopupShowAction, GURL const&, bool)
0x000000011ad98f91	(Google Chrome Framework -extension_action_view_controller.cc:219 )	ExtensionActionViewController::ExecuteAction(ExtensionActionViewController::PopupShowAction, bool)
0x0000000119c50ac0	(Google Chrome Framework -menu_button.cc:129 )	views::MenuButton::Activate(ui::Event const*)
0x0000000119c50e64	(Google Chrome Framework -menu_button.cc:206 )	views::MenuButton::OnMouseReleased(ui::MouseEvent const&)
0x0000000119c2db18	(Google Chrome Framework -ink_drop_host_view.cc:279 )	views::InkDropHostView::OnMouseEvent(ui::MouseEvent*)
0x0000000118e60df9	(Google Chrome Framework -event_handler.cc:32 )	ui::EventHandler::OnEvent(ui::Event*)
0x0000000118e64481	(Google Chrome Framework -scoped_target_handler.cc:32 )	ui::ScopedTargetHandler::OnEvent(ui::Event*)
0x0000000118e6078d	(Google Chrome Framework -event_dispatcher.cc:191 )	ui::EventDispatcher::ProcessEvent(ui::EventTarget*, ui::Event*)
0x0000000118e605c3	(Google Chrome Framework -event_dispatcher.cc:86 )	ui::EventDispatcherDelegate::DispatchEvent(ui::EventTarget*, ui::Event*)
0x0000000119cb18ec	(Google Chrome Framework -root_view.cc:444 )	views::internal::RootView::OnMouseReleased(ui::MouseEvent const&)
0x0000000119cb6da5	(Google Chrome Framework -widget.cc:1225 )	views::Widget::OnMouseEvent(ui::MouseEvent*)
0x0000000119c3ca2c	(Google Chrome Framework -bridged_content_view.mm:703 )	-[BridgedContentView mouseEvent:]
0x0000000119c434a1	(Google Chrome Framework -cocoa_mouse_capture.mm:91 )	___ZN5views17CocoaMouseCapture14ActiveEventTap4InitEv_block_invoke
0x00007fff31de3f55	(AppKit + 0x001abf55 )	_NSSendEventToObservers
0x00007fff3240d8fb	(AppKit + 0x007d58fb )	-[NSApplication(NSEvent) sendEvent:]
0x000000011803d73b	(Google Chrome Framework -chrome_browser_application_mac.mm:328 )	__34-[BrowserCrApplication sendEvent:]_block_invoke
0x0000000118418279	(Google Chrome Framework + 0x02296279 )	base::mac::CallWithEHFrame(void () block_pointer)
0x000000011803d3e6	(Google Chrome Framework -chrome_browser_application_mac.mm:311 )	-[BrowserCrApplication sendEvent:]
0x00007fff31c6e8b4	(AppKit + 0x000368b4 )	-[NSApplication run]
0x00000001184285fb	(Google Chrome Framework -message_pump_mac.mm:808 )	base::MessagePumpNSApplication::DoRun(base::MessagePump::Delegate*)
0x000000011842717d	(Google Chrome Framework -message_pump_mac.mm:184 )	base::MessagePumpCFRunLoopBase::Run(base::MessagePump::Delegate*)
0x0000000118449cb4	(Google Chrome Framework -run_loop.cc:102 )	<name omitted>
0x000000011804354a	(Google Chrome Framework -chrome_browser_main.cc:2086 )	ChromeBrowserMainParts::MainMessageLoopRun(int*)
0x0000000116c293b3	(Google Chrome Framework -browser_main_loop.cc:1034 )	content::BrowserMainLoop::RunMainMessageLoopParts()
0x0000000116c2bb01	(Google Chrome Framework -browser_main_runner_impl.cc:162 )	content::BrowserMainRunnerImpl::Run()
0x0000000116c25e6a	(Google Chrome Framework -browser_main.cc:47 )	content::BrowserMain(content::MainFunctionParams const&)
0x0000000117ff71d7	(Google Chrome Framework -content_main_runner_impl.cc:596 )	content::ContentMainRunnerImpl::Run(bool)
0x00000001198a717c	(Google Chrome Framework -main.cc:472 )	service_manager::Main(service_manager::MainParams const&)
0x0000000117ff6283	(Google Chrome Framework -content_main.cc:19 )	content::ContentMain(content::ContentMainParams const&)
0x00000001161856f2	(Google Chrome Framework -chrome_main.cc:101 )	ChromeMain
0x000000010e741dd0	(Google Chrome -chrome_exe_main_mac.cc:101 )	main
0x00007fff5c51b014	(libdyld.dylib + 0x00001014 )	start

Yeah, this is WontFix - the involved code is getting removed in 71 but we won't merge the removals back to 69 or 70.

We could merge the about:flags removals. That would merge cleanly.

 Issue 884558  has been merged into this issue.

Issue 883286 has been merged into this issue.

confirmed that this bug is caused by #secondary-ui-md - #top-ui-md set to "normal" can ALSO cause instability.

 Issue 886945  has been merged into this issue.

 Issue 891914  has been merged into this issue.

If the involved code is being removed, how does a user of Stable continue to opt-out of the undesired Material interface in 71+ ?

#14: They don't - we do not retain the old versions of our UI indefinitely behind flags. We only left it in M70 because removing it would have made merges to the M70 release branch more complex.

what a shame, as the new UI is far less compact, and unsightly.