As I understood it, that when I have several trades open to get one lacking card, as soon as the first trade for this card is successful, the other open trades for this card should get auto-withdrawn. Well, this feature has failed on me multiple times by now.
I tend to sometimes make several trade offers (partially including different cards from my side) to get one card. After the first time, when the other trades weren’t auto-withdrawn, I tried to stay aware and thus was able to withdraw open trades manually, after I had received the wanted card, but at three times by now I ended up with two duplicates of the desired card, because of this bug. It also made me trade away some cherished cards unnecessarily, that I’d rather have kept for a duplicate of a card, that I only wanted to get once. This is really annoying!
Update: This time it worked again and auto-withdrew two trades after one was successful. But right now I don’t fully trust that feature.