DSR Support (Game always ignore native resolution)

Hello,

I always had this problem. And its not normal, because in most other games it doesn't act like this.

Problem:
When DSR enabled, i usally have all possible options enabled (up to 5k on my 2k Monitor).
But sometimes i want to tab out the game, and go back, then i am in windowed mode. When i press ALT + Enter (for entering full screen mode), the game sets me into the highest DSR setting (5k in my case), instead of my real native resolution.

This issue also happends when a pick the "Full Screen" mode in the UI of the game options. The game think that that is my full screen. Which is not. If i want to play at 5k, please let me choose it.
Everytime it heats up my pc, and is very annoying. I hoped that it will be fixed by the devs.

Thanks.