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Not any specific steps, get a size 31 brush, paint a bit and eventually I see some lines.
At the end near the bottom right one appears. I mouse over it in a circular fashion without clicking to make it disappear.
If you have layer edges displayed, when the blue bounds are drawn again it forces them all to disappear. I mainly noticed because I killed preferences to test something else.
Windows Vista 32 bit
With "snap to grid" enabled, this is really noticeable/reproducible.