Version 53.0.2785.154 (64-bit)
Platform 8530.96.0 (Official Build) stable-channel link
Firmware Google_Link.2695.1.169

I decided to change the picture associated with my @google account. It was displayed at Chrome OS login screen as well as the hangout avatar, gmail avatar, etc., it has been around for at least six years.

started with modifying the chrome os login screen setting (clicked on the icon in the lower right corner of the chrome OS page when taskbar is displayed, changed the picture . It turns out to be the only place where it changed. 

Went on to gmail settings, changed the picture there to the same new image.

The icon in the top right of the gmail page still did not change. Clicked on the icon, then on the "my account" button. See the same old picture in the middle of the shield on the top of the screen - replaced the image (this was the third setting modification).

Noticed that the icon in the top right of the gmail page still has not changed. It turns out that clicking on it allows to modify it (fourth setting).

each modification suggested editing the picture.

Seriously, guys, four different places?

Somehow it used to be one place - I sure did not set the old picture in more than one location back then.