See an old bug  issue 225955  for some context background.

Another example I cited in code is: "a demo device on a store shelf. One customer walks up to device and enables some a11y features, leaving the device in a "funny" state (high contrast, screen magnifier, spoken feedback enabled). After some time, another customer may feel the device
looks "broken".

Code is in: https://cs.chromium.org/chromium/src/ash/policy/policy_recommendation_restorer.h?q=recommendation_re&sq=package:chromium&g=0&l=34

Right now, it only manages five prefs: large cursor, high contrast, fullscreen magnifier, spoken feedback, virtual keyboard. But now, there are more a11y features listed on signin screen. These five prefs apparently are not synced to date. 

Propose to manage all available a11y features on signin screen, but open to pm's decision on it. Console could control `Turn off accessibility settings on sign-in screen upon logout` to fix the above related problems.