Is it OK to marked this as a partial duplicate ?
#9160 is only referring to big picture mode, while the primary window being transparent is a severe regression in its own right.

In addition to Ubuntu, Fedora 37 (xfce) is also concerned with steam beta active :
"Fedora release 37 (Thirty Seven)" (64 bit)
X Window Manager: Xfwm4
Steam Runtime Version: steam-runtime_0.20230509.49499
Video Card:
Driver: NVIDIA Corporation NVIDIA GeForce RTX 2060/PCIe/SSE2
Driver Version: 4.6.0 NVIDIA 530.41.03
** Note : the settings window is not affected. **

• reverting back to vanilla steam client for now as a workaround.

Also affected on ArchLinux, latest version of steam & nvidia from the repos.

I found a workaround: Restarting the display manager (sddm in my case) fixes the issue. This is probably caused by the Nvidia driver messing up its context after putting the computer to sleep.

Disabling FXAA fixes this for me. Looks like it's an issue with NVIDIA's driver's implementation of FXAA with electron apps in general.

https://github.com/ValveSoftware/steam-for-linux/issues/9160#issuecomment-1593898872

hashtag me too. I sent Steam Support a ticket about it, and told them what's wrong, and they led me to github database. Basically my issue is the same, but I don't remember the UI being transparent so long ago. It feels like it only happened after the last update. Anyway, I've posted on reddit too. Here is the system check result I got, which has an entry about the graphics driver:
"graphics-details" : { "x11/vulkan" : { "renderer" : "llvmpipe (LLVM 15.0.6, 256 bits)", "version" : "Mesa 22.2.5 (LLVM 15.0.6)", "issues" : [ "software-rendering", "cannot-draw" ], "exit-status" : 1, "devices" : [ { "name" : "llvmpipe (LLVM 15.0.6, 256 bits)", "api-version" : "1.3.224", "vulkan-driver-id" : 13, "driver-name" : "llvmpipe", "driver-version" : "Mesa 22.2.5 (LLVM 15.0.6)", "vendor-id" : "0x10005", "device-id" : "0", "type" : "cpu", "messages" : [ "Vulkan not supported on given X window" ], "issues" : [ "software-rendering", "cannot-draw"
It seems like my card is not supported, but support didn't tell me anything about my card with Nvidia 390.157 driver being dropped from support. They also told me only latest Ubuntu version with Unity, Gnome or KDE desktop is supported, and I'm using cinnamon mint

I FOUND A SOLUTION:
https://www.reddit.com/r/linuxmint/comments/14nmzu3/comment/jq93yws/?utm_source=share&utm_medium=web2x&context=3

• [ ] You just make a desktop icon of Steam from the app menu,
• [ ] copy that to the /'User'/.local/share/applications/ folder,
• [ ] right click on the icon, select properties,
• [ ] add at the end of the 'command' line -vgui, (the apostrophe should follow it)
• [ ] and then launch it by clicking on it or typing exec sh -c 'STEAM_FRAME_FORCE_CLOSE=1 steam %U -vgui'

This will launch the Steam client in the old GUI mode!!! Please, a round of applause to sir Champster24 there on my reddit thread.

Hey. I've received another fix for it. Go to NVIDIA x server settings, and disable FXAA under antialiasing settings.

Disabling FXAA worked for me (Fedora 38, nvidia binary drivers)

@alexis-belmonte I think you're almost right — this occurs for me on a machine that has sleep disabled, so I think the nvidia driver is messing up after a display sleep, not a computer sleep.

Can anyone else reproduce this on a freshly-booted machine after running xset dpms force off?

This is ona Desktop machine, where no powersaving is active :)

Also, Steam was always transparent, it had nothing to do with computer sleeping.

HTH

Adding -vgui to return to old interface worked for me. Don't want to configure mi FXAA properties. Thanks to @Epicathery178

Strangely, the transparent interface worked fine until last update. May be they configured alpha to 50% or something like that.

hmm I'm having this same issue too I'm running with Nvidia Driver 535.86 on Linux Mint (Cinnamon)

Hey. I've received another fix for it. Go to NVIDIA x server settings, and disable FXAA under antialiasing settings.

Update from my end I did this and it worked (fixed) for my end thanks for posting the fix