This functionality is completely removed since 2013-12-14 18:23 PST, see: bugs 38966 and 913734 Note: If you've reached this page from a message box in Firefox or another Mozilla product, try using keyboard shortcuts for the Cut, Copy, and Paste commands: Copy: Ctrl+C or Ctrl+Insert (command+C on Mac) Paste: Ctrl+V or Shift+Insert (command+V on Mac) Cut: Ctrl+X or Shift+Delete (command+X on Mac) T
![Midas editor module security preferences - Mozilla | MDN](https://cdn-ak-scissors.b.st-hatena.com/image/square/e51bd6dc33a667d35eb4146698a198e55ff92d6e/height=288;version=1;width=512/https%3A%2F%2Fdeveloper.mozilla.org%2Fstatic%2Fimg%2Fopengraph-logo.72382e605ce3.png)