Battery optimization not selectable in Cyanogenmod 13 I just installed Cyanogenmod 13 and a couple of Google Apps (the OpenGApps Micro Package) on a Nexus 4 mako Device. Trying to disable battery optimization for some apps, I found that in the batter settings screen I cannot select Battery optimization from the action menu. The item is simply not clickable. One can reach the battery optimization screen from Settings -&gt; Apps -&gt; Settings -&gt; battery optimization, too, but then the selector going from not optimized to all apps is not clickable. 

Am I missing some dependency or is this a bug? I have recovered some system settings by TitaniumBackup, maybe something was incompatible with CM? (Before, I ran an AOSP marshmallow rom, too).
Also running CM13 on Nexus 4, with the difference being no GAPPS. The 2 entry points you mentioned works just fine here.

Try a clean flash without restoring settings using TiBu - CM uses a slightly different settings provider from AOSP and it might prove incompatible indeed.