Bug in reaction automapper leads to infinite loop

[lithom]

When using the JEditableChemistryView with a specific reactant and product, then mapping atoms causes an infinite loop:

IDCodes in attached file:
idcodes.txt

Mapping the first atom outside the ring from educt to product causes the following output:

MCS Result: R=0 P=0 #Atoms=3
MCS Result: R=0 P=0 #Atoms=3
MCS Result: R=0 P=0 #Atoms=3
MCS Result: R=0 P=0 #Atoms=3
.
... continues forever

Code to reproduce:

public class test_a {
    public static void main(String args[]) {
        IDCodeParser icp = new IDCodeParser();
        StereoMolecule reactant = new StereoMolecule();
        StereoMolecule product  = new StereoMolecule();
        icp.parse(reactant, "dmtD@@QIeyVUZh@@@pcKTwCJ`");
        icp.parse(product, "dk\\D@@SHheIhTf{SZj`@`@vhYWS@");
        JEditableChemistryView view_a = new JEditableChemistryView(1);
        Reaction rxn = new Reaction();
        rxn.setFragment(true);
        rxn.addReactant(reactant);
        rxn.addProduct(product);
        view_a.setContent(rxn);
        JFrame fi = new JFrame();
        fi.getContentPane().setLayout(new BorderLayout());
        fi.getContentPane().add(view_a,BorderLayout.CENTER);
        fi.setSize(800,600);
        fi.setVisible(true);
    }
}