ChromeOS / Crostini, ToT

What steps will reproduce the problem?
(1) activate crostini, install gtk-3-examples there
(2) open gtk3-demo
(3) double click 'dialogs and message boxes'

What is the expected result?
a dialog pops up, the window focus moves to the new dialog

What happens instead?
a dialog pops up, but it does not get keyboard focus.
The dialog responds to mouse events or key events actually, but it has no visual clue. Also this confuses the IME bridge (for issue 826614)



Please use labels and text to provide additional information.

If this is a regression (i.e., worked before), please consider using the
bisect tool (https://www.chromium.org/developers/bisect-builds-py) to help
us identify the root cause and more rapidly triage the issue.

For graphics-related bugs, please copy/paste the contents of the about:gpu
page at the end of this report.