Open topped, stackable, molded plastic container, which is generally rectangular with a bottom and first and second pairs (2,3; 4,5) of parallel upright walls joined to the bottom and at corners via corner structures, wherein each corner structure comprises a substantially diagonal and upright wall section which, seen in top view, extends diagonally between adjoining upright walls and blends into said upright walls to define the contour of a containment space of the container; characterized in that each corner structure further comprises: - a top wall extending outward from an upper end of the diagonal and upright wall section; and - a hollow tubular post extending vertically downward from said top wall, said hollow tubular post being spaced from said diagonal and upright wall section, wherein the top wall has a hole aligned with the hollow tubular post; - wherein multiple, e.g. at least three, vertical stacking ribs (15a-15g) are arranged circumferentially spaced about the hollow tubular post, each stacking rib having a vertical inner end joined to said hollow tubular post, ∘ wherein at least one, preferably two, of said stacking ribs (15a, 15g) have a vertical outer end joined to said diagonal and upright wall section and/or to said adjoining upright wall section; and ∘ wherein each of said stacking ribs has a lower end, said lower ends being located in a common plane; wherein said tubular post has a protruding stacking pin portion extending downward beyond said common plane of the stacking rib lower ends; such that - in a stack - the pin portion of an upper container is received through the hole in the top wall of the corner structure of a lower container onto which said upper container is stacked. - a top wall extending outward from an upper end of the diagonal and upright wall section; and - a hollow tubular post extending vertically downward from said top wall, said hollow tubular post being spaced from said diagonal and upright wall section, wherein the top wall has a hole aligned with the hollow tubular post; - wherein multiple, e.g. at least three, vertical stacking ribs (15a-15g) are arranged circumferentially spaced about the hollow tubular post, each stacking rib having a vertical inner end joined to said hollow tubular post, ∘ wherein at least one, preferably two, of said stacking ribs (15a, 15g) have a vertical outer end joined to said diagonal and upright wall section and/or to said adjoining upright wall section; and ∘ wherein each of said stacking ribs has a lower end, said lower ends being located in a common plane; wherein said tubular post has a protruding stacking pin portion extending downward beyond said common plane of the stacking rib lower ends; such that - in a stack - the pin portion of an upper container is received through the hole in the top wall of the corner structure of a lower container onto which said upper container is stacked. ∘ wherein at least one, preferably two, of said stacking ribs (15a, 15g) have a vertical outer end joined to said diagonal and upright wall section and/or to said adjoining upright wall section; and ∘ wherein each of said stacking ribs has a lower end, said lower ends being located in a common plane;