Unable to select cards from hand

When using Battle Line, it became impossible to select a card: when clicking on a card, the cursor each time because the (upper-left) corner of an apparently huge selection red rectangle.

Not long before, one card had disappeared from the board. Maybe this is related?

I’m not sure how to reproduce this strange behavior, but I thought it might be useful to mention it.

(I guess that saving the game and restarting it may have solved the interface issue, but I haven’t tried. Could the disappeared card somehow have moved inadvertently somewhere very far in the hand window?)