Unsure if this is purposeful or not, but having plotBorder give a three sided border is a little confusing. It kind of gives the impression that the rectangle runs longer than the length of the chart and just isn't being rendered properly. I feel like the border should either run on all four sides, or alternatively, run on the sides related to the axis that the plot band runs on (x axis plot bands on "left" and "right" side, y axis plot bands on the "top" and "bottom" of the rectangle).
A plotBand on either the x or y axis would draw a rectangle, and adding a border would show a visible border on all four sides (or two of them to indicate the bounds of that area).
Border only appears on three sides
Thank you for your feedback. Internally all four sides currently have a border, but because of z-indexing only three sides have visible borders.
Fixed #5909, `plotBand` border was only drawn on three out of four si…
…des of the rectangle.