Torches cannot be placed on top of glass panes or iron bars

As can be seen through the screenshots, the top of a glass pane has a 2x2 area of pixels on top, which should be enough to support a torch, having a 2x2 base. However, they cannot be placed on them without using /setblock (which I used for the images).

May be considered WAI, but felt this was worth reporting anyway given the changes to transparent blocks in recent snapshots.