The code that ensures bendpoints are preserved when the model is updated is a bit too simple, and preserves source/target anchors as well as intermediate bendpoints when the connected node moves.
The source/target anchor (i.e. first/last routing point or bendpoint) should be updated or erased when the corresponding node moves, to avoid converting anchors to bendpoints on each move operation, resulting in an accumulation of invalid intermediate points:
The code that ensures bendpoints are preserved when the model is updated is a bit too simple, and preserves source/target anchors as well as intermediate bendpoints when the connected node moves.
The source/target anchor (i.e. first/last routing point or bendpoint) should be updated or erased when the corresponding node moves, to avoid converting anchors to bendpoints on each move operation, resulting in an accumulation of invalid intermediate points: