[Verizon Samsung Galaxy S7 Guides, News, & Discussi] lugnut2099:
I'll throw a curveball in here, what the heck. I'm on a US Cellular S7 Edge and I think I can report that, whatever's causing the force-closing of apps is NOT Xposed. I don't have it installed at all yet, performed the root as described on page one on Friday. Though I skipped the Xposed install, I did flash the S7_or_S7_Edge_Fixes_Debloater_V15.zip and left it there for the time being (no kernel adjustments, no other changes). Lag was apparent right away (as well as seeming to be running kinda hot), but other than a couple times, nothing too bad in terms of major slowdown or other oddities. On Sunday afternoon I rebooted, possibly for the first time since the last flash of the Debloater file, and got the force close problem. It didn't actually register to me at first and I thought I'd just somehow triggered opening up the Application Manager on my own, since I was preoccupied by a bunch of other stuff when I looked down and caught it. Not long after I rebooted again, keeping an eye on it, and sure enough it did it again. (Mine seems to start with killing Youtube, since I don't have Snapchat installed...)

Here's the seeming difference, though - It's attempted to do this every time I've rebooted ever since (several times), but so far, I've also been able to stop its killing spree by just hitting the home key or anything else. After that I can just "close all" and it seems to go on with normal operations. Also, no sign of a bootloop or any other startup issues yet and I haven't had the issue with wi-fi settings not saving after reboots, so I didn't do any build.prop editing. I saw the "unauthorized actions" nag immediately after gaining root, but by the time I'd flashed the debloater file, I don't recall ever seeing it again - ie, I didn't disable SecurityLogAgent and it disappeared anyway. I thought maybe the debloat file had done this on its own, but as I saw later, maybe not...

Over the course of the night I've used Titanium to freeze many of the suggested options on the "Debloat a S7/Edge" thread (just freezes, no actual deletions, and while I didn't freeze every process on the lists, I didn't add any new ones of my own choosing either). Result so far there is what seems to be a definite uptick in speed and a return to more normal temperatures, but the attempted force-closing still occurs. (And on this round I finally did kill off SecurityLogAgent, which still showed as active, as well as SecurityPolicyUpdates).

So...any guesses now as to what could be the cause? I'd been waiting to install Xposed just to see how it seemed to be working, but it looks like it happens anyway, so I'll probably toss it on there sometime today. (And hope it doesn't trigger the boot loop...)

My build number shows as MMB29M.G935R4TYU2APE2 (I know PE2 has been reported as not working out as well as PE1, but I didn't really take note until I'd already done it and wasn't sure if it would necessarily apply to USCC variants anyway, so oh well...). And ooh, I can report another force-close attempt just now! While looking for that version number I accidentally tapped "Device name" and as soon as I do, it spawns the force-closes. And once again, just pressing back or home will stop it.

If I get brave enough to try Xposed later, I'll be sure to follow up with an update if anything else odd happens afterwards.