In MacOS Big Sur, I figured out an app (downloaded from internet) normally can not access
~/Desktop/ folders directly. When it tries to access those folders at the first time, there will be a popup window to ask for permission and the permission can be setup in System Preferences > Security & Privacy > Privacy > Files and Folders.
Edited: It seems my bad description makes people confused (sorry about my English). I will put two screenshots here to clarify what I mean:
The above screenshot appears when the app
iTerm2 tries to access
~/Downloads folder at the first time in Big Sur. (basically when I execute
ls ~/Downloads/ commands in iTerm2)
The above screenshot is where I can change the folders privacy setup.
But, today, I downloaded an app (it's a downloading tool) and installed it by dragging it to
/Applications folder. (the same way I installed
iTerm2) I tried to use that tool to download a file to
~/Downloads folder and the file can be downloaded and written to
~/Downloads folder directly without any permission requirement. It can also display/read all the files in the
~/Downloads folder. I checked the Privacy setup in System Preferences and it does NOT have that app setup too.
I am very confused how can that app read/write the file to ~/Downloads without requiring a privacy permission on the protected folder. I thought those protected folders were protected and were not allowed to be read/write before granting privacy permission. But I was wrong. (Note that, later I found out Google Chrome App can read/write those protected folders too without asking this privacy permission. File > Open File > Choose any files inside the three protected folders)
PS1: I haven't mentioned the "downloading tool app" name here because that is a non-English app. If anyone consider I should give the name to get a better help, just let me know. Thanks.
PS2: This is a fresh install of MacOS Big Sur. (Not a upgraded system)
PS3: The "downloading tool app" is a GUI app. (NOT a CML app).
PS4: I just find out the
Google Chrome.app downloaded from https://chrome.google.com can write to (save file to)
~/Downloads/ folder directly without requiring any privacy permission too. This is weird. Why does
VLC require privacy permission to do any read/write to those protected folders but google chrome does NOT need to require anything.