Discord

What works

Voice chat after some workarounds

Text Chat

Generally most features

What does not

Voice chat doesn't work unless you disable qwave.dll in wine dll overrides

Video streaming

Client says it's corrupt

Workarounds

Described above.

What was not tested

I didn't test game store features (is that even still a thing)

Nitro

Hardware tested

Graphics:

• GPU: Nvidia
• Driver: proprietary

Additional Comments

Stable 54146 (224561b)
Host 0.0.305
Windows Server 2008 R2 / 7 64-Bit (6.1.7601)

Ran in 64bit prefix with winetricks for dotnet 4.5 set to Windows 7 and also a 32bit prefix. Not sure if needed but it seemed to not run without it however I didn't do too much testing in this regard.
I need to uncheck "Allow the window manager decorate the windows" under the Graphics tab, otherwise the Close button will not appear (at least on plasma) and it seems that cursor events do not register/the cursor will disappear randomly. The application will then seem to fully launch properly, however joining a voice channel causes the application to crash and reload (in an infinite loop as it will keep retrying). The error in console for this is as follows:
wine: Call from 0x7b031dbf to unimplemented function qwave.dll.QOSAddSocketToFlow, aborting
wine: Unimplemented function qwave.dll.QOSAddSocketToFlow called at address 7B031DBF (thread 00f0), starting debugger...
If you go to DLL Overrides in winecfg and disable qwave.dll, then the application will launch successfully, and you can even join a voice channel at this point, but there will be a message at the top that says "Discord is corrupt". If you proceed to remove the DLL override at this point this message will disappear but not all functionality will be available until you reload (which, at that point, voice wont connect again). If you do not reload, you will soon notice that some functionality is missing or unusable (specifically, video streaming and the ability to toggle on or off "Automatically determine input sensitivity"). If you plan to adjust your input sensitivity, you will need to configure it before setting the DLL override. 
The client seems to think it is running in the browser despite some Desktop only features still appearing (like video streaming) even though it's not functional. Video streaming will fully detect your windows and monitors separately (something Discord for Linux doesn't even do) however if you begin to stream it will not work. I presume this has to do with qwave.dll not working properly but I didn't investigate this fully.
Discord RPC (Rich Presence; the feature that shows game state on your status) *does* work with games running in the same wine prefix (this is why I even bothered trying discord in wine). This was tested with osu! and it worked perfectly.
All in all, I give this a bronze rating as there's a few kinks to work out, but hopefully they can be fixed in the future.