Abnormal termination if you select
the Crop command without a current image
The Crop command is enabled if you select a thumbnail when there is no
current image, i.e. when both window panes are showing thumbnails.
If you select the Crop command, it should crop the selected thumbnail.
Instead, the software terminates abnormally.
Double-click the thumbnail to make it the current image before
selecting the Crop command.
Corrected in V4.2.