I created a new user account on Windows 10 whose type is "standard user" and in which the User Account Control (UAC) setting is set to "Always notify". To test the privileges, I download GitHub Desktop and it installed itself without asking any question whatsoever. There was no prompt for password from the administrator account, only a splash screen saying that "GitHub Desktop is being installed" and a window asking for GitHub credentials after that. The app was indeed successfully installed because it was listed in the "App & Features" list, but I don't see why Windows would allow it to happen.
What am I missing? And how do I make sure applications always ask for permission before being installed? For instance, if it was a misclick, GitHub Desktop would install itself anyway, without giving me a chance to correct my mistake or even cancel the process.