osx / macOS : GNU Emacs: How to Restore File System Access in macOS Catalina

• https://emacs.stackexchange.com/questions/53026/how-to-restore-file-system-access-in-macos-catalina
• https://emacs.stackexchange.com/questions/53904/why-cant-i-list-the-contents-of-desktop-on-macos-using-dired
• https://github.com/caldwell/build-emacs/issues/84#issuecomment-545754668

I actually added Emacs (and /usr/bin/ruby – /usr/ is a a hidden folder, so tell the Finder to allow access to the hidden folder /usr/ temporarily like this: Shift-Cmd-“.”) here:

• System Preferences > Security & Privacy > Privacy > Full Disk Access