I had to erase my hard drive and restore it from backups. The one thing I’m having trouble restoring is the drive’s custom icon. I have a Time Machine backup that includes the .VolumeIcon.icns file that was in the root directory of the hard drive, but this file itself doesn’t have a custom icon, so it’s not possible to do the usual “copy the icon from one file’s Get Info window and paste it into the other file’s Get Info window” routine.
How can I take the icon from a .icns file and “paste” it onto another folder or file?