On Windows: Shift + Alt + Up/Down. On Mac: Shift + Option + Up/Down. On Ubuntu: Ctrl + Shift + Alt + Up/Down.
{ "key": "shift+alt+down", "command": "editor.action.copyLinesDownAction", "when": "editorTextFocus" }, { "key": "shift+alt+up", "command": "editor.action.copyLinesUpAction", "when": "editorTextFocus" },