I c&p from the wiki in
this topic.
If you use IronworksIronworks.jpg from Intrigue to try and gain a card but reveal TraderTrader.jpg to gain a SilverSilver.jpg instead, the Ironworks does not give you any bonus(es) for the card you didn't actually gain.
If you use Ironworks from Intrigue to try and gain a card but reveal Trader to gain a Silver instead, the Ironworks does not give you any bonus(es) for the card you didn't actually gain.
So in ff, {{Card|$card}} gets replaced by $card$card.jpg. Don't know if something can be done against this.
Edit: Short examination in Firebug shows that it also copies the alt-tag:
<span>
<img width="200" height="320" src="/images/thumb/5/5d/Silver.jpg/200px-Silver.jpg" alt="Silver.jpg">
</span>
change the alt, it also changes the c&p. But to fix this would requiere alt="", which is not really good style, especially for robots.