Can't Alt-Tab Back To Game Since Update 10.5

[Twistank]

Ever since the 10.5.1 update I am unable to go back to the game once I do the ALT-TAB. I can still hear the sound and I can mouse click and hear myself firing in the game but screen just don't go up. I am forced to kill the game and restart and it is really annoying as I often have to alt-tab. Before the update ALT-TAB was very easy and smooth in Warframe. 

[Krokar]

LEt me say since 10.5, I get crashed to DT alolt when ALT-Tabbing during ANY loading screen.

[Qurossu]

I've been having this same issue since I started playing with update 11. Really annoying since I'm quite used to alt-tabbing often and get called up randomly on skype quite a bit. Just happened to me when I was making decent progress with Soloing Alad V/Zanuka. Forced to bring up task manager and kill the program each time. DE should fix these REALLY basic functions ASAP, it leaves a real bad stink when these things don't get fixed quick. It's not there yet though, but it's getting there.

[Twistank]

During the talks with support, I realized that this problem has something to do with multicore option. There are 2 fixes that should made it a bit easier  but still it is a problem that will not go away easy it seems.

 

1) Obviously, turn off the multicore support and then ALT-TAB is working not very well, but it is working, sometimes game crash.

2) Set your game display in Window mode on any resolution, or the Borderless Fulscreen mode locked on 1920x1080 resolution, ALT-TAB works well in these modes.