When viewing a file or diff, you can change its configuration using the Config button on the toolbar or by using the [F12] keyboard shortcut.

This will open the config dialog where you can change the config for the current viewer or differ.

Viewers and differs for the various file types each have their own config dialog. The config for a differ is identical to the config for the corresponding viewer, but with a few more options specific to diffing.

Whenever a config is changed, the viewer or differ must be reloaded, which will discard any unsaved changes.

Setting the default configs

Ideally, you’ll spend all of your time working with your files rather than fiddling with configs. To make sure this is the case, DiffPlug has a powerful but simple preferences system to make sure that you start out with the config you want.

When a file is first opened, it uses its differ default config. To view and change the default configs, open the Preferences window from the menu bar under Help - Preferences. Under DiffPlug - Differ defaults you can see the defaults for each file type. Because the config for a viewer is a strict subset of the config for a differ, each config is shown for the differ and then reused for the viewer.

Using a custom config

Even after you have set your differ defaults according to your needs, you still might find that you need to change a config, for example to trade accuracy for speed in an especially large folder diff.

For this, you can use the Open custom or Diff custom operation from the context menu. This will open the config to be used before the viewer or differ is opened.

In some cases you might want to use this particular config over and over, but only for this particular file or this particular file extension. To do this, you can use the Add to known extensions using filter option at the bottom-left.

Known extensions

The known extensions mechanism is used to keep track of the various extension filters you have created. Anytime a file or pair of files is opened, it is first checked against these extension filters. If none of these filters matches the file, then it will use the default config.

To see and modify the list of known extensions, open the Preferences window from the menu bar under Help - Preferences, then select the Known extensions element on the left.

The known extensions page maintains a list of every set of extensions which has a custom config. If you click an extension, its associated config will appear on the right for viewing and editing.