Screen dims except navigation bar On my Yoga tab (B8080-F) with Android 4.4.2 all of a sudden screen got dimmed except for the navigation menu, where it remains bright as set in the display settings. If I change brightness manually, the dimmed part of the screen also changes and if I restart, the brightness is normal but shortly after the startup screen gets dimmed again, so I am suspecting an app that can make use of screen overlay to cause this. I have uninstalled FB messenger (it uses overlay notifications) but no luck. Any idea how to figure out what app is cause this annoyance?
UPDATE: Well as it often hapens, I found out solution right after posting this question. Using instructions from this post Determine which app is drawing on top of other apps? I have identified the offending package to be com.lenovo.powercenterhd which is Lenovo Power Manager, where at some point I have apparently enabled Protection Glassess feature, which dims the main screen. After turning it off, brightness went back to normal.