Chrome Version       : 51.0.2704.79
OS Version: 8172.47.0
URLs (if applicable) :
Other browsers tested:

  Add OK or FAIL after other browsers where you have tested this issue:
     Safari 5:
  Firefox 4.x:
     IE 7/8/9:


What steps will reproduce the problem?
1. After auto-update the sign-in screen stopped showing the user-names (user-picture widgets) anymore despite that option being enabled in settings. The widgets seem hidden as when I press tab-key to cycle through UI elements in sign-in screen they eventually re-appear one at a time.

What is the expected result?
User-accounts should be visible on sign-in screen when that option is enabled.

What happens instead of that?
They are hidden. To user it may look like all accounts have been deleted from the machine.

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

UserAgentString: Mozilla/5.0 (X11; CrOS i686 8172.47.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.79 Safari/537.36

Chromebook is a Samsung XE500C21.

 According to the about-box the version is 51.0.2704.79
 Plattform 8172.47.0 (Official Build) stable-channel x86-alex_he 
 Firmware Alex.03.61.0735.0056G3.0021

Problem started Friday-ish after auto-update of chromebook. Likely a bug in the new version.