The Gradebook Ajax autosave functionality can be used both with editing turned on or off. In this case, we are looking at editing turned on, where you can input any grades which would be auto-saved (background turn to orange) every time you change student or column, without having to click on update at the end (it's not functional if Ajax's working anyway) or enter on the keyboard. However, if you lock a column or an individual grade, the autosave does not work anymore, and must click enter after each entered grade or after entering all to save. The autosave also fails to initialise if there are any ungraded items (GRADE_TYPE_TEXT) in the course's gradebook.