How can we force MacOS to forget that a specific file was downloaded from the web?

Question

MacOS remember that things were downloaded. MacOS refuse to open or execute script downloaded and prompt the famous message:

cannot be opened because it is from an unidentified developer.

Can I make MacOS forget this file was downloaded?

I know I can do a right-click -> open. But I want to avoid the additional hassle for specific files. The protection is particularly annoying for bash script you may want to open in a text editor multiple time. I'm well aware of the risk of exectuting a downloaded script.

I also know I can remove the protection altogether, but I don't want that.

In the info of the files, you have the information but it's not editable:

Answer 1

You can delete the download source by running

xattr -d com.apple.metadata:kMDItemWhereFroms FILENAME

To also remove the quarantine flag use

xattr -d com.apple.quarantine FILENAME

PS: If FILENAME is an application (ends in .app), add -r to have the attributes removed from all files within the application.

Answer 2

To create an app that can do this from the GUI, launch Automator. Select New -> Application

In the Actions Library, go to Utilities and select "Run Shell Script" In the Pass Input drop-down menu, select Select "As arguments"

Where it says echo "$f", replace it with xattr -d -r com.apple.metadata:kMDItemWhereFroms $f xattr -d -r com.apple.quarantine $f

So the content of the shell script is for f in "$@" do xattr -d -r com.apple.metadata:kMDItemWhereFroms $f xattr -d -r com.apple.quarantine $f done

Save the app as "DeQuarantine.app" in a location you find convenient for Drag-and-drop (I put it on the Desktop).

Then, when you have downloaded files you want to remove the warnings from, drop them on this app.