From the right-click menu options in the Devices View, you can Compare Configurations on any two devices.
Once the devices are selected from the listing, right-click, then select the Compare Configs option. This is helpful for comparing device states, and for a detailed view of the configuration.
At the Devices States Comparison window, note the differences. You can highlight, and then click the state (for example, in the above graphic you would click running on the cat2923-4 device) to view the entire Config.
You can now view the Previous Change or the Next Change of configurations on this device.