Clearing notes/descritpion of item does not remove note

When clearing notes on an item that has notes entered, the change does not take effect.

Steps to reproduce:

1) for any item, add or edit information and add text into the "description of item" field.

2) Save changes / add item

3) Edit item that has notes/description of item

4) clear the entire field, such that the subtext "optional ..." appears

5) save changes

-> previous text still appears