Because discord portable lets you use your account from any device while downloading portable apps or using it on a cross-website server. You can just access your discord account from any device quickly. When you need to access your discord apps urgently, but you don’t have your original device with you. Which boosts apps to start up faster than before. But when you use a portable one, your system had to use RAM twice. Because when you use your main apps, your system had to depend on RAM once. When you use discord portable, it starts faster than the original apps.
