It's unusual these days (I would have thought) for a level of Undo history to not be available for text editing.
I often find that the User Notes are easily warped if pressing undo. Strange characters can be inserted, or whole sections wiped.
Similarly, it would appear that entering Hebrew can be problematic, with the direction of entering text inconsistent (e.g., entering a qal + waw consecutive of the verb to be).
I can of course work around this by editing the contents in Text Edit, but then the formatting and colours may not be preserved when pasting the finished note back.
So better text editing support in general would be a great plus (even inline editing of notes).