The top pane lists all files in the selected folders, while the bottom pane shows the differences between two versions of the selected file (see Compare files). The differences are displayed in the Differences Viewer for Folders:
IntelliJ IDEA lets you compare files in two folders against their file size, content, or timestamp. When you are comparing two files, or a file with the Cliboard contents, you can swap sides by clicking on the toolbar.
To assign shortcuts to the apply and append actions, open the Keymap page of the IDE settings Ctrl+Alt+S and locate these actions under Version Control Systems | Diff & Merge. Productivity tips Assign shortcuts for 'apply' and 'append' Select a modified file anywhere in the Version Control tool window.
