FreeFileSync takes usability very seriously. Therefore drag & drop is supported in various situations:
Example:
drag & drop a directory onto the main window to set the directory for comparison
drag & drop a file onto the main window to set the directory for comparison
drag & drop *.ffs_gui files onto the main window to load the configuration contained
drag & drop *.ffs_batch files onto the main window to display and edit the batch configuration
drag & drop *.ffs_batch files onto the batch dialog to display and edit the batch configuration