Big Picture comeback after streaming game on Monitor with different ratio (i.e.: 1920*1200 vs 1080p TV) does not Stream the right part of the screen

[ghost]

Your system information

• Steam client version (build number or date): Feb 23rd 2017
• Distribution (e.g. Ubuntu): Archlinux
• Opted into Steam client beta?: [Yes/No] Yes
• Have you checked for system updates?: [Yes/No] Yes
• System: Configuration

Please describe your issue in as much detail as possible:

Steam Big picture launchs as expected on my 1920*1200 monitor, with black padding on top & bottom of the screen, and it is correctly streamed to my TV via Steam Link. I can launch games and it is correctly streamed too. When I leave the game however, then Big Picture mode loose his padding, so I can see my desktop underneath. This causes the problem of the picture below, meaning that not all of Big Picture frame is streamed, and I see a part of my desktop on the TV. I expect to have the black padding when I come back to Big Picture, and that only Big Picture frame is streamed to the Link.

Video of the problem in action with Steam Link and a windowed game

Video of the problem in action without Steam Link with a full screen game

In this blurry photo you can see the state of the TV, with a part of my desktop on top, and not the bottom of Big Picture frame (buttons indications are cut).

Steps for reproducing this issue:

1. Have a 1920*1200 Monitor to launch Big Picture on
2. See the black padding on top & on the bottom of the screen
3. Launch a game (via Steam Link or not, in windowed mode or not)
4. Exit the game
5. Notice the black padding has disappeared
6. Notice that the stream contains only part of Big Picture frame and a little of the Desktop on the top

[ghost]

@slouken do you need any inputs from me?