Here is how to install the Twitch Desktop App in Wine.
It is highly advised to be using a staging version of wine. Less issues overall.
WINEPREFIX=/home/user/path/to/prefix WINEARCH=win64 wineboot WINEPREFIX=/home/user/path/to/prefix WINEARCH=win64 winetricks corefonts WINEPREFIX=/home/user/path/to/prefix WINEARCH=win64 winetricks dotnet46
INSTALL TWITCH APP
To install Twitch, execute the following :
WINEPREFIX=/home/user/path/to/prefix wine TwitchInstaller.exe
This will eventually complete. Pay attention during the installer to where it wants to install ("C:\users\username\Application Data\Twitch"). I change it to another location ("C:\Twitch").
After installation you may have an issue getting Twitch to see a game to manage its addons. If you have not modified your Wine virtual drive letters, you should be able to do a full scan for games and have it see games outside the prefix (RIFT, ESO, WoW). If worse comes to worse, symlink them to your prefix. Its rare that the latter is needed, but I have been told this was a workaround for a few folks.
Videos are choppy at the moment. Known issue. Perhaps a newer version of wine will do the trick.
I have not had good luck enabling DXVK in lutris for this prefix. Things work as intended otherwise.