Sometimes using the contact map causes a green-yellow bond line (like the one used for cysteine) to appear between two segments, usually not cysteine.

If I open the contact map and move my cursor on and off it, this line goes away.

But if I change puzzles without doing this, the line persists.

Here it is in 941:
http://fold.it/portal/files/chatimg/irc_343528_1405732926.png

Here it is in 942, from an isoleucine to an alanine:
http://fold.it/portal/files/chatimg/irc_343528_1405733128.png

It doesn't seem to affect play, just looks strange because it stretches clear across the protein where I don't expect it.