You can also lock an app from autostarting with PowerMaster. Settings>Battery>PowerMaster>Auto-start manager>Preloaded and deselect YouTube, Google Photos etc.
So you think that the problem is powermaster? Apps what gets enabled by something is: YouTube, Photos and with firmware 193, Google Chrome. I dosnt need Photos and i use Youtube with firefox and also browse with that, so i dont need chrome either.
I was thinking that a possible solution could be PowerMaster. Verify that those apps are disabled from auto-starting and see if you notice any changes. I'll know more when I hear back from the software team.
Now google chrome gets updated, so its get enabled but the app dosnt show up on powermaster app list at all. So it isnt a solution for this behavior. And i rebooted the z6, but still that chrome dosnt show up on powermaster.