Two questions:(1) add a note entry (2) note's capacity

I have two questions. 1. Can Mendeley add an editable note? If I have a new research idea, I would edit this note file at Mendeley and always stick this note to the top of any list. 2. It looks like that capacity of notes to any entry is not so big. I would write a long note to a paper sometimes. In a rare case, the length of notes is longer than the paper.