I just noticed an update is available for the Linux version of Discord for Linux, version 0.0.7. But as I clicked the update icon in Discord, I almost lost my vision!
This is how the update menu looks like on version 0.0.6. Now I have no idea if this fixed in 0.0.7 because updates don't come every couple of minutes. But if it isn't, I would very much like to see this menu to be dark.