Requests permission to begin editing text.
- macOS 10.0+
The text object requesting permission to begin editing.
true if the text object should proceed to make changes. If the delegate returns
false, the text object abandons the editing operation.
The default behavior of this method is to return the value obtained from
control(_:, unless the delegate doesn’t respond to that method, in which case it returns
true, thereby allowing text editing to proceed.