Viewing Manifest Files

PrefEdit contains a browser for macOS preference manifest files which allows you to decode the complete contents of a manifest in a user-friendly way. It is not necessary to work with the XML code or the raw property list of the manifest.

As mentioned in the introduction, manifest files are usually part of application bundles, so you cannot use the standard methods to navigate to a file. To open a manifest, it is recommended to use the following method:

  1. Select the application whose manifest you like to open in the Finder, then right-click on the application’s icon and select the item Show Package Contents in the context menu.
  2. In the new window displaying the contents of the package, open the folder Contents, then its subfolder Resources.
  3. Locate the manifest file in the folder. It should be found using the naming rules mentioned in the introduction.
  4. Double-click the manifest file or drag it onto the icon of PrefEdit. The latter is preferred it the manifest is actually a folder with multi-lingual resources.

If you know the POSIX path of a manifest file in advance, you can also use the following alternative:

  1. In PrefEdit, select the menu item File > Open, or press the key combination ⌘ + O.
  2. In the Open panel, press the key combination ⌘ + ⇧ + G to open the sheet Go to the folder.
  3. Enter the path of the manifest file into the field, then continue with the instructions above for opening an application package.
Manifest file
Manifest file

PrefEdit will open a new document window which displays the decoded contents of the manifest. The window contains the following elements:

After selecting a manifest key in the table, the lower part of the window will display detail information about the key and its preference setting:

Preference settings support several data types for values, as discussed before. For two particular aspects, preference manifests can be more specific in describing what data type to expect:

If specified, the allowed value range for a preference setting is either noted as an interval, for example 2 … 5 (meaning that the values 2, 3, 4, 5 are allowed), or it is shown as a pop-up menu listing all permitted values line by line. You can open the pop-up menu to view the complete list. Note that selecting any of the values has no effect.

Union Policy Keys (UPKs)

PrefEdit can also decode entries of preference manifests which are not directly related to preference settings, but which describe a policy the MCX technology should use when overriding settings which must be merged with settings already present. Such manifest entries are called Union Policy Keys or UPKs.

A union policy is used by MCX to combine values of already present settings to produce a new setting when the management actions takes place. There can be one or more input settings whose names are listed as input keys, and one single output setting, merging the values either into an array or a dictionary.

In case a manifest entry represents a union policy, a button Show Union Policy will appear instead of the default value for a setting. Pressing this button will open a detail sheet which describes the policy:

Union Policy Display
Union Policy Display