How to keep an app from "Dozing"?

I wish to keep my Gmail app from Dozing so under Battery Optimization I configured it to not be optimized. That doesn't work. After an hour or so (maybe less) I am not alerted to any incoming emails (and Gmail doesn't sync) until I wake up the phone. Gmail works fine except when Dozing. Totally stock unrooted Android 6.0 on Tmo. Phone and all apps work great. I wonder if I need to configure any of the other system apps to not Doze in order to allow Gmail to not Doze?

Any ideas?

Is the windows 10 upgrade easy or should I keep waiting for windows 10 stock

I ordered a windows 10 version of this tablet over 3 weeks ago and it just isn't coming in stock where I ordered it but I see that they do have a windows 8.1 version in stock. From what I have seen upgrading to windows 10 doesn't look like a lot of fun. Can you comment on your experience and if you think I should just keep waiting for one with windows 10 already installed to come into stock.

Summoners war keep closing

Anyone playing this game and the game keep detect unauthorized program detected and closed? I suspect is becoz of root

Not satisfied with CM 12 how to back to stock but keep root

Hi!
I sincerely didn't thought that there would be an official 5.1.1 rom. So there it is. In the meanwhile I switched to CM but the performance and specially of the camera is not to live with.

I officially unlocked the bootloader and installed twrp.

How can I install the stock rom 14.6.A.0.368 (5.1.1) and keep root. Or how can I get it back afterwards?

Thanks!!!