Added the ability to switch between vertical and horizontal panel layout in File Diff and File Merge windows. Previously, file panels in these windows were shown side-by-side with a vertical splitter between them. You can now toggle between that mode and horizontal mode, where panels are shown above and below. This is useful when your files have long lines and you can’t see the entire line without horizontally scrolling.

We now detect binary files (files containing a NUL byte) and give a warning and stop. This keeps us from showing artifically truncated files in the windows.

Made the “multi-line intra-line analysis” adjustable for performance reasons. A setting for this can be found on the “Detail Level” page of the Options dialog. There is a large discussion on this feature in the DiffMerge manual.

Added External Tool feature. DiffMerge can now be configured to invoke an external, third-party tool for various types of files (based upon the file suffixes). This allows you, for example, to select special tools for XML or Word documents. You can then double-click on a pair of files in a folder window and have the external tool launched to compare them. For more details see the DiffMerge Manual.