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View -> Sort -> Rating
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Use the scroll bar to show the first cell.
Set the painter tool to paint 3 stars.
Paint one cell, let’s say, the 10th cell.
PROBLEM: sometimes it paints 2 or 3 cells instead of one.
It becomes more evident using the Wacom tablet pen.
Using the mouse produces the error doing this: click and hold the mouse button pressed on a cell, now move a little the pointer. If you do this, all the cells will be painted.