there is a difference between single click and double click on the notes field, or any field for that matter on the Portfolio editor. NOTE: double click, not just click twice. Double clicking starts editing, where as single click just puts focus on the field, and if you start typing, whatever you are typing will become the new value overwriting previous value. That is intended.
As for you not seeing the data when typing, I have no idea how you are managing that. Are you using Large Fonts settings? Anything else unusual about your setup?