This still happens. Here's an APNG animation (won't work in IE, Chrome or Safari; will work in Firefox or Opera) to illustrate the issue:
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If the door is fully closed, the room on the other side is not drawn at all, and instead the sky is drawn behind the bars. As soon as a part of the room can be seen below the opening door, the room can be seen as expected behind the bars.
So the issue is that the renderer doesn't know that transparent doors like this can be seen through even when closed.