Another quick and easy one:

0) Just to be able to see the difference, add a note to a cell and leave another
cell without a note.

1) Select (left-click) the cell with the note.

2) Move the mouse cursor to the cell without the note (or any other cell for
that matter) and right-click while hovering over it to call its context menu.

3) The appearance of the context menu entry "show/display note" at the bottom of
the menu list reveals that the presented context menu is that of the last
selected (and outlined/marked) cell, opposed to the expected context menu of the
cell that the mouse cursor was hovering over when right-click was executed.

This is contrary to user expectation and behavior in other modules of current
OOo (like OOoWriter) as well as of that of pre-1.0.x versions of Calc.
It is hence confusing and highly error-prone, especially under regular working
conditions.

If this is intentional behavior in order to prevent unmarking of a previously
marked range of cells, then make the righ-click respone act differently when
only one cell is selected or when the cursor is within the selected/marked range
 of cells. In the case of only one selected/marked cell, the context menu should
always be that of the cell the cursor "points" to when the user invokes the
context menu.