A more complete version of Discord's Dark mode via CSS injection
STEP 1:
To begin, you need to ensure that you can inject CSS code into your current version of Discord. To do this you must locate the file titled index.js. To do this, from windows, press your windows key and enter in %appdata%. From there you can locate the file by navigating to discord\0.0.x(x being your current version of discord)\modules\discord_rpc\ Open the index.js file with some kind of text editor such as Notepad++ or Sublime (Not the regular notepad application). At the bottom of the code you will copy and paste the text found in the inject.js file (provided by Globi)
STEP 2:
Download and move the custom.css file into your discord_rpc folder. This will have all of the actual changes made to your client.
STEP 3:
Simply refresh your Discord client and all changes should be made. Feel free to explore around the app and report any issues to @DeVanteEB on Twitter! Enjoy!
Video instructions(also provided by Globi) can be found here in case you struggle with any of these steps: https://streamable.com/4rdy6
STEP 4:
I've included an extras.css file that contains a few extra CSS tweaks regarding emoji and blocked users, but are separate from DarkMode+. Feel free to add the code from there to your custom.css file if interested in applying it.